I think a common problem for developers/consultants (and others working a lot with computers) we have to install a lot of programs (beta, alfa releases) and after a while (a short time) the performance on the laptop PC is not so good anymore.
I talked with DELL support and they told me when disk free space is lower than 50 %, performance sink 30 %!!!
Reinstall the PC is the best way to get back the performance on the PC, but it is painful, doing backups ….
But now I have bought me an extra disk and replaced it with the DVD player in my laptop. I then moved all data to this extra disk and reinstall Windows XP.
I have now all data on this extra disk (D:), on the first disk (C:) I have only windows XP and programs.
I have also moved the outlook data file to the extra disk (D:), I found out how to Move your Outlook data file to another location
It is now easy to reinstall the computer!!
I am now also able to buy me an extra disk and easy install MacOS (or linux) on the PC and have access to the data disk, cool!!