Question about disk cleanup

[beerabuser30]

I ran the windows disk clean up utility on Vista 64 bit. It came up with 42 GIGS of previous windows installation. I noticed my hard drive seemed like it had more memory taken up then there should have been. Should I delete it? I don't want to delete anything important but I am not sure what to do.

 

[kimsland]

I usually use a program called CCleaner
In default settings (ie the way it is when first installed) it will not remove anything you need

Whereas the "windows disk clean up utility", may in fact remove files that you have not used in a long time, but still would like to keep