I think wheels on a cab are a bad idea, if i had to roll the thing out everytime I wanted to play with it, it would just never get used. My, is that if its in a closet, it will stay in the closet and not get much use.
FWIW, just build a LCD bar top with a 19 inch screen, there are a ton of those. I would make sure I got a good screen though, a lot of LCD's laid vertical like that look like ass because of the viewing angles.