So, there is one computer in our house that is pretty old. 8 years maybe? 6? Something like that. Not the problem. The problem is:
IT RUNS LIKE A DINOSAUR! A FAT ONE!
It literally takes 3-5 minutes to log in to someone's account...
It's on XP SP2. 1.60ghz processor, 256MB of RAM.
What are the best guides and tweaking programs that you suggest I use on the computer to make it run faster? Not just any guides. Good ones. And programs too please.

By the way, I have just installed CCleaner and TuneXP 1.5 so don't suggest those.