if you can afford it go for somehtign between a AMD XP 2200+ - 2600+ thoroughbread. (from 2400+ and up its getting harder to find them).
or you can wiate for the AMD Hammer cores that will wreck havoc in everything in its path of CPU destruction
![Biggrin user added image](images2/smilies/biggrin.png)
and if all of those are too much for you, go for a palimino core AthlonXP 1900+ - 2100+. (these are getting pretty cheap now days)
But really your CPU doesnt need an upgrading for a while, dont bother unless your extremely serious about this, and using that computer for some jobs.
as for ram... 512 is satisfactory, but 1 gig is better
![Smile user added image](images2/smilies/smile.png)
if i was you the only thing ide upgrade is my video card, and maybe if you been saving that allowence for a while another stick of ram
![Smile user added image](images2/smilies/smile.png)
good luck man