Go for 2gb, 4 from Dell is a rip off. You can always upgrade it yourself later. Counterstrike it will definitely play. Crysis it will play but not with max settings. 4 or 5 hours on battery? No. You'll probably get 1.5 hours of gaming time on battery. Normal run time will be around 4 though. You won't get the best performance while on battery power. The graphics card turns itself to lower frequencies to conserve battery life. You can change that but it will hurt battery life. That laptop is a good choice. Remember to search for coupons.