So how to make your computer faster again without buying a new machine?
Firstly, check how much memory your machine has. Windows always has liked to use lots of memory and modern operating systems like XP and Vista are especially greedy. If your machine has less than 2Gb of RAM memory, it's time to treat it and you to more.
Upgrading your memory to this level will make near enough everything on your computer run faster. If Windows doesn't have enough memory to work with, it will use space on your hard disk as an alternative. But hard disks are lots, lots slower than regular memory.
A memory upgrade is simple enough to do yourself - there are plenty of tutorials online to show you how - or your local computer store will be happy to help you for a small fee. The whole operation should be over quickly - it will probably take you longer to unscrew the screws on the case than it will to upgrade the RAM.
If it's only print jobs that are running slow, do the same treatment for your printer if it's possible. Color lasers especially will appreciate any extra memory you give them and will allow Windows to pass them across more of the printing job, freeing up your machine for other tasks.
If that still doesn't do enough to make your computer faster, there are other things you can try as well.