You can use a VGA output adapter for the Xbox 360 which can scale to whatever resolution and you can use HDMI for the PS3. I would suggest you use a 1080P monitor of around 24" in size if you can afford it as they are the sweet spot in terms of size/price atm.
As for brands, take your pick between Asus, LG, Samsung etc or any of the name brands anyway because I doubt the brand will effect much from your perspective.
Tease.







