1. 40gb -7200rpm harddisk drives, Seaget or Maxtor are the same, same price too
2. 256mb ddr333 modules -your clockspeed 333 will reduce to 226 depends on the motherboard. If you have money buy a "Kingstone" brand its expensive yet better and has 3yrs. warranty.
3. Pentium 2.4 Ghz - if your a gamer then go for Pentium, the computer graphics are smoother and faster
4. Video Card - Geforce FX5200 (for DirectX9 support) 128-bit, 128mb, dont buy 256mb its expensive besides this is for video and graphics editing
5. Motherboard - Intel Board, buy the OEM rather than the BOX because its cheaper
6. Casing - Buy a See-Through Casing its Cool
7. Mouse - Dont buy wireless mouse, it really sucks and "TechTV" admitted it. Logitech and A4tech with mousewheel are the best
8. Monitor- 17"LG Flatron F700B, this monitor really makes a difference, really flat
9. Speakers- Go for Altec Lansing or Creative. They've got nice Sub woofers,making your room a warzone
10. Webcam -- Buy a Creative Cam, try it before you buy it, test for the clarity
11. Keyboard-Logitech
12. UPS- go for "Giant"
13. Samsung CD_RW/ DVD combo drive

Note: If trying to invest on a gaming platform PC buy a higher a processor, go for the best there is, your game zone will last for almost 3yrs before upgrading.