64 MB of RAM? Geeeeee.....
Then it's really time you did a good upgrade.
Upgrade to at least 256 MB of RAM. Especially if you're using Windows XP.
What's the CPU type? Get at least a 1 GHz Pentium 3 processor, or an equivalent Athlon processor.
If you wouldn't mind, the best thing to do currently would be to buy a whole new computer system. You can easily get PCs that'll seem like greased lightning to you for less than 500 quid if you shop around.