Well, since you want all of those consoles to be able to plug in, I say you don't actually go with PC screen. The reasoning for this is lack of video ports, meaning you probably wouldn't be able to hook up any of the non-HD consoles without some sort of possibly spendy conversion piece.
That being the case, you mentioned you don't really have a budget, but price is the major difference in a lot of tvs. Looking at the Best Buy 21-29" category, Dynex is going to be one of your cheapest brands, but they do receive really good reviews. In this case a 1080p 24" is $249.99, 720p 22" is $199.99, 720p 26" is $279.99.
If you're looking for a product that might be a little more dependable, and the ratings are even higher (about .2 higher on a 5.0 scale), you could look at a Samsung, but these will run more in the $399.99 to $499.99 range for similar products.
All of these tvs are going to be 60Hz refresh rate, which is fine for what you are doing on them, especially with the older consoles.
There are a couple of other brands in this size range, such as Toshiba, but I'm not 100% sure about their quality.
Personally, I'd buy this one: http://www.bestbuy.com/site/Dynex™ - 24" Class / 1080p / 60Hz / LCD HDTV/9848048.p?id=1218183918195&skuId=9848048 ...that's the 24" Dynex for $249.99, I just can't see paying any more than that for this size tv when this one offers everything the others offer and has great reviews.
Money can't buy happiness. Just video games, which make me happy.
