Get the first one, the Acer. It's faster for gaming, and for LCD's, the native resolution for almost all LCD's 17" and 19" is 1280x1024. For most 15" LCD's it's 1024x768. There are a few LCD's with 1600x1200, but they're hard to come across. 1280x1024 is a good resolution for gaming, so you should be fine with that.
AMD 64 3200+ Newcastle@ 2.2Ghz
1GB (1x1GB) OCZ Performance Series
ATI X700 Pro 256MB OC\'d 475/525
OCZ Modstream 520W
Samsung 914v 19\" 12ms LCD
SB X-Fi w/ Logitech Z 5300e