Thanks for the advice chris. If the reinstall doesn't fix things I'll try the memtest iso as suggested. I've already got everything important on this computer backed up, plus the windows installation from my school moves all of the documents into a windows.old folder.
Not sure if this is doing a complete reformat or not though. When I have installed from a windows xp disk in the past I have seen installation options that include "reformat".
The windows 7 install from my school has the two options mentioned previously:
"upgrade"
or
"reinstall"
We shall see what happens....
