Re: Vegas advice needed...
We always try to stay somewhere on the MGM/New York-New York/Excaliber corner and then just hop around to those casinos while we are there.
There is also a (most of the time working) light rail style tram that goes from the MGM up to the Sahara, which covers most of the strip. So if you want to go up to the Bellagio/Paris/Caesars area, you can.
All of the major intersections on the strip have raised walkways, so you can cross the street without having to wait at a stop light or fear idiots running you down.
While you are at the MGM - check out a few of the nearby casinos - Luxor, Mandalay Bay & New York New York. All have bars, restaurants and stuff to do that is unique to that casino and quite fun.
New York-New York's Nine Fine Irishman and Coyote Ugly pubs are personal favorites.
The only ones outside that area I would say are "must sees" are the Bellagio, Paris-Las Vegas and the Venetian. All are amazing works of architecture and a site to see.