Well, for basic computing, Celeron kicks butt. It's affordable, and gets the job done, but compared to its brother, the Pentium 4, it's kinda crippled...
FSB -
Celeron: 533Mhz
P4: 800Mhz
Cache -
Celeron 16KB for Celeron, 256KB for Celeron D
P4: 1-2MB depending on model
Depending on what you are doing with the computer, the processor should be fine.