That is a Socket 478 motherboard. It has been pretty much obsolete since 2005 or so. You are limited to Pentium 4 and Celeron processors that are Socket 478. Save your money and upgrade.....it is not worth trying to make a build out of that old thing.
Sorry but I don't agree with you anort.
If he only plans on surfing the web and doing light work, then spending $20 dollars on a new p4 is the best route.
I recently upgraded my 12 year old p3 rig(700MHz) to a new p3(1GHz) for only $10 that back in the day would have cost $700, and hell I even played counter-strike on that with the old processor.
@fermin446 - Go ahead and google your motherboard to find a list of compatible cpu's, then hunt for deal on ebay, i'm sure you will find one. Good luck!