Just to fill in a few details...
This is a huge resort that was built in phases, hence all the different sections. I heard that the Courts was one of the first sections built and that these are the largest units. The second last built I believe is the Lakes. The Cascades I believe is the newest -- one of the few with elevators and a zero entry pool if that is important to you. Other section names I can think of are Fountains I and II and Spas. I'm sure there are others I'm leaving out.
Yes, Courts was first, and the upper units are very large, although the 2nd bedroom is pretty small (only 2 single beds). Full disclose - we own a week in Courts. After Courts came the Falls, Spas, Palms, and Springs sections. Building then continued across Meadow Creek Drive on Fountains, Fountains II, and Lakes. The last section completed was Cascades, back on the East side of MCD.
The resort does have two fairly distinct areas (almost like villages), but the facilities are open to all. The nine sections share 7 pools; Cascades pool isn't technically zero entry; there is a single step down, but there are little fountains in the shallow area that the youngsters love. Pretty sure that either Fountains or Lakes has zero entry, but we don't venture to the other side often.
Elevators are only in the 4 story buildings in Lakes and Cascades. All other sections are 2 to 3 stories with walk ups. It really isn't that bad. The only time I find it bothersome is when BBQ'ing. This year we were in a 3rd level unit in Springs. I forgot a couple of things and had to make a total of 6 trips up and down the stairs before dinner was done!

A bit of planning would have helped!
Every single section, though, has recently (might be a few not done yet -- you can call and find out) gone though a major remodel -- like gutting the whole place putting in granite counter tops, etc (complete and total remodel). This brings this resort (every single section) right up there with the best timeshare resorts in the area. What too is so wonderful about this place is that much thought and care went into the landscaping in every section. Unlike most of the timeshare resorts in the area, here, there are little lakes and lovely landscaping all over meaning your patio or balcony view will be lovely for sitting out -- not a parking lot view. We use our patio and/or balcony alot, so this is important to us and something we really appreciate about the Vistana. All the pools we've checked out I thought were really nice. What's not to love about this place? Oh and we're a tennis playing family -- so their great clay tennis courts really appeal to us too.
Courts is the last section to be renovated and is underway now. We were unable to stay in our own unit this year because of the this. The section will be complete in September, and it is highly unlikely that you will get an unrenovated unit now as most of the Courts units are closed for renovations, or have been recently completed. Maybe 24 old Courts villas still open as of now, and that number decreasing weekly. At this time you are highly unlikely to get an unrenovated unit.
I never really thought about the views, but this is very true. Most units front onto the parking, but the balconies/patios all look over landscaped areas. Very pleasant! One plus of the older sections is that you park right at your door, in the larger buildings you may have to walk a bit further to get to the elevator.
I don't really know about how likely you are to get a certain section. I've stayed here four times and three out of the four times I got the section I requested. Two of the times I think they really wanted to go out of their way to accomodate me and with good reason -- the one time I had a broken leg and wanted a section with elevators (who is going to make a person with crutches climb stairs). The other time, I had extended family at the Fountains and wanted to be as close as possible to them (who isn't going to put families together at Christmas if they can). (The one time I didn't get my request -- I asked for a renovated unit, but didn't get it -- still liked what I got -- but other condo resorts in the area would have been nicer), I think that this was partly because everyone was requesting rennovated units, and at that time only the Lakes was rennovated.
You can request a particular section through Diamond Lane request. The resort is always eager to satisfy guests, but be reasonable. It is much more difficult to give everyone what they want during busy weeks when the resort is full up. If you are travelling during a less busy period, there is a very good chance you can get what you request. That said, there is very little to request. There really isn't a bad section at the resort. Some areas are quieter than others, some closer to the action; but they are all great clean and large units.
I personally would be happy in any renovated section (which I think at this point is probably all of them). If you do not like the unit you are assigned, take the time to go back to the front desk and ask for other choices. Staff seems very accomodating and helpful.