It was essentially written to counter some misinformation and misunderstandings about the Order of St Benedict that I'd heard, so doesn't pretend to be either comprehensive or systematic!
I do plan to do more parts of this though (starting of the question of whether there is such a thing as 'the order of St Benedict'!), so do let me know if you have any particular questions you'd like answered about Benedictine spirituality or the nature of the Benedictine Order/monastic practices, and I'll see what I can do!
Please do feel free to provide corrections or additional information, or to comment and disagree on my take on the subject!
1. Do Benedictine nuns have to practice papal enclosure?
No, not necessarily. Strict papal enclosure was imposed on all female religious after the Council of Trent as a way of responding to Protestant propaganda about religious, but (unlike many other Orders such as Franciscan, Dominican and Carmelite nuns) it was not part of the original charism.
St Benedict certainly encouraged a strict division from the world for both his monks and nuns, but a good case can be made that the charism was originally for the 'mixed life' rather than strictly contemplative (his monks acted as chaplains to nearby communities, and their immediate successors, both monks and nuns, included many missionaries; and St Benedict's emphasis on hospitality is pretty much incompatible with strict enclosure) of the type allowed for under current canon law as 'constitutional enclosure'.
In fact the most famous story we have about the first Benedictine nuns concerns St Scholastica's annual trip to visit her brother St Benedict at the foot of his monastery, something certainly not possible under papal enclosure.
St Benedict's Rule (except for the section on priests) in principle applies equally to men and women, and includes provisions on how to behave outside the monastery, rituals for long journeys, and instructions on dealing with guests within the monastic enclosure.
In the nineteenth century revival of monasticism, the charism split two ways - in the US Benedictine nuns became actives, and lost the right to solemn profession, whereas most of their European sisters accepted papal enclosure. Today canon law allows more leeway, and while some traditional nuns (such as Le Barroux) continue the tradition of strict papal enclosure, others (such as Jouques), while maintaining the forms of enclosure (grille and parlour so forth) take turns at extern duties, and practice hospitality in the spirit of the Rule.
2. How is the seeming affluence of some Benedictines compatible with the vow of poverty?
Actually, Benedictines don't technically make a vow of poverty (though it is certainly encompassed in the vows they do make) - they actually promise stability, conversion of life, and obedience, in accordance with the Rule of St Benedict.
And there is an interesting difference between Benedictines and Franciscans. St Francis wanted his friars to both be poor and look poor - to wear patched habits and so forth. St Benedict by contrast instructed his monks to wear the patched habits within the monastery - but when going outside on a journey, to be given a nicer outfit stored up for the purpose.
Similarly, Benedictines generally wear choir cowls over their normal habit in Church to present a nicer face to the outside world. Benedictine poverty and austerity, in other words, was to be practiced in secret within the monastery, but not to be made obvious to the outside world. So don't make assumptions about how the monks or nuns are living based on the little glimpses you get to see!
Secondly, though, religious poverty in the Benedictine tradition is about collective ownership of goods - no solemnly professed monk or nun 'owns' anything personally, anything they use is supposed to be allocated to them by the abbot/abbess on the basis of need only. That means that if you give a monk a gift, the abbot decides whether or not he gets it, or it goes to someone else.
3. Can the monastery buy up lots of nice stuff under the guise of common ownership?
If we are talking expensive tvs/entertainment equipment, aeroplanes (yes one new Cistercian community, now defunct, actually owned a plane) and the like, then I personally think that is totally inconsistent with the Rule.
St Benedict, after all, specifies a certain degree of austerity - no more clothes than are needed for the locality and type of work done for example.
But the Rule does assume the monastery will spend up big on necessary things - like books in particular, since reading and study is a big part of the life.
He also put a lot of emphasis on adapting the Rule of the monastery to individual needs - if some needed more things in order to persevere in the life, then the abbot should allow what was necessary (and others should not be jealous of whatever privileges they were allowed), since perseverance is far more important than uniformity.
And whereas St Dominic, for example, specified that the chapels of his order should not be filled with expensive items, prohibiting for example the use of silk, Benedictines have always prized beauty, particularly in the worship of God (Cistercians of course, split off in the more austere school of monastic life, with whitewashed chapels instead of wall paintings and so forth).
Benedictines have also traditionally tried to make their monasteries appear attractive - they live in them for life, remember, not wondering about as friars and others do, and shouldn't often leave them. They do not generally get four week overseas holidays a year; or to go out to visit art galleries or attend a concert, or have a meal. Instead their recreation periods are strictly regulated, and are generally communal (typically a group walk). So if they are allowed an occasional more relaxed form of entertainment in the monastery as a special treat, or spend some communal money on entertainment, that's not (necessarily) inconsistent with poverty.
By way of context, it's worth knowing that the most ascetic Order of them all, the Carthusians, filled their monasteries with some of the greatest art works of the middle ages until the Reformation (and subsequent waves of anti-catholic forces) destroyed so many of them.
4. Do the monks/nuns eat the same food as guests?
St Benedict's Rule puts a lot of emphasis on hospitality. The monks were supposed to maintain a separate kitchen (where meat could be served, in contrast to the diet specified for the monastery itself), and the abbot or a senior monk was to dine with the guests. Even the internal fasts of the monastery were to take second place to the duty of hospitality, with an instruction to break the fast in order to dine with a new arrival.
It's an approach that has firm roots in the desert monk tradition, where two visiting monks were scandalized by the rich meal offered to them by a famous monk - they didn't realize that what he offered them was very far from his normal fare.
Within the monastery proper, the Rule specifies a regime of either one or two meals a day depending on the season (but able to be modified by the abbot if the needs of the time and place demand it), with no meat of four-hoofed animals (so birds and fish are ok). The monastic fasts specified by the Rule are generally about how many meals and when the meal is taken (in Lent, the one meal is delayed until the evening, rather than being mid-afternoon for example) rather than quantity consumed.
St Benedict's emphasis was on moderation in food (and other things) rather than strict asceticism (he specifically allows wine with meals for example, even while noting that many see it as unsuitable for monks), and on ensuring that everyone has enough to eat to cope with the other rigours of the life. In this light, over time the Rule has generally been modified somewhat - most monasteries do allow some light breakfast, and many eat at least some red meat (Dom Gueranger didn't think frenchmen could survive without it, so his Solesmes Congregation set the trend)! But most also have regular stricter fasts.
Some men's monasteries allow male guests to eat in the refectory, so you do actually get to see what the monks eat. But elsewhere, if the religious are feeding you, don't assume - what you are consuming in the guesthouse may not be what the monks or nuns are eating (or not eating)!