Enough monitor for gaming is opinion. but anything 19" with about 1600x1200 would be to me a good gaming monitor.
But my opinion on whats enough for gaming falls no shorter then the 24" i already have D: but for me this isnt even enough.
My bottom line enough for gaming monitor is this one
http://www.samsung.com/PressCenter/PressRelease/PressRelease.asp?seq=20061010_0000293416
Like i said though its all opinion for me enough for gaming is large,high resolution, and super high quality picture. which of course is also controled by a video card so yeah. just keep in mind the ms rating they give is BS. Mine right now is rated at 6ms but its more like 10. It has a nice contrast ratio and brightness. The resolution is a bit small but that doesnt matter unless you care. I just hope the screen isnt one of those shinny glass covered LCD or your going to hate that thing when it turns into a mirror. Cant say anything about the maker NEVER heard of them before.