Looks good but i dont see an OS in there, would need to be 64-bit for the 4Gigs of ram.
For Gaming there is some debate other which is better between 22" and 20" inch as they are the some resouloution as far as i know. Ask in the monitors section where they know better. My understanding is that for Gaming the best monitors are still the big old CRT's which can be had for peanuts nowadays, if youve have room and can stand the idea of CRT they can't be beaten.
Oh also do you need a mouse and keyboard with that?