overclocking newbe specs

hey thinks guys or gals for the help. I didn't know anybody would actually answer me, wow, this is an awesome website. Anyway, The parts I'm going to use for my first computer build is:

Asus p4s800 sis648fx chipset mobo socket 478
pentium 2.4(800fsb) northwood core
gigabyte nvidia geforce fx5700 256mb video card
and 512mb of some kind of memory(which one, i don't know any suggestions)

this computer is for my family but in the future when the cpu starts to get a little old I would like to be able to overclock it, or just to try it for fun. We dont do much gaming(unless it's like need for speed or some fun game)

HERE'S SOME SPEC ON EVERYTHING i'M GOING TO GET . I'm really trying to keep my budget under $400.00. Basically what I'm doing is upgrading the computer I have with a new Mob,cpu, video card, case, and memory. heres my specs tell me what you think.

1)40 gig maxtor hard drive(already have in computer)
2)asus p4s800 sis648fx chipset socket 478( 533, 800fsb)
3)pentium 2.4 or 2.8 ghz (800fsb)
4)nVidia Geforce fx5700 128mb video card( we're not big gamers but we like to play some, {need for speed}, {tony hawk}
5)512 mb memory from corsair
6} linkwood black/silver atx midtower 400w supply

None of these items are to pricy but have good reviews on new egg. The Mobo is $70.00, case is $35.00 nad has plenty of cooling option, 2 fans on back and one on side and one on front. I'll be putting one more whole on the side for another fan, and probally want use the front. Like i said i am cash hendered so i'm trying to find the best for my money. Give me some ideas on what you think about these product. I'll be posting these specs in every area of the community for each part I'm getting.