very slow

Yes there is. It does not always make it faster, but it helps and should be done once a week
Ccleaner.
In addition, defrag. I like and use auslogics, but you can used the built in defragger.
The right antivirus helps, too. There are some that are resource hogs like Norton. Best to use one with a light footprint, like Microsoft Security Essentials.

I thank you for your rep. I almost forgot that we have a great tutorial on the subject. Let me know how you make out.
Speed Up the Performance of Vista