|All new computers & laptops will come with Windows 7. The lower end ones will have the 32-bit version, all others will have 64-bit.|
You should get at least 4GB RAM.
Hard drive size will vary. Lower end laptops with have 160GB, others will have 250GB, 320GB, 500GB or larger.
There are dozens of choices in processors, it depends on how much you're willing to spend. Avoid the low end single core CPUs & go for a dual core. For Intel CPUs, Core i7 > Core i5 > Core i3 > Core 2 Duo > Pentium dual core. There are also choices from AMD.
For gaming, you need good graphics & that's what's going to drive up the price. Gaming laptops are NOT cheap. There are 100's of different graphics choices - stay away from ALL Intel graphics as they are NOT good for gaming. Look for ATI Radeon or nVidia GeForce graphics. Here's a table of almost 300 laptop graphics "cards" listed from best to worst. I suggest you stay within the top 150: