Compress drive to save disk space?

Compress drive to save disk space?
Does anyone know if doing this to your hard drive in windows Windows XP Pro SP1 affects the dvd burning process and if so how.

I would call this a bad idea. It will mean that evrything on the disk is compressed which means if you want to open somthing or run a program it will have to uncompress it before anything will happen. If this is a program/ game then it will have alot of files to uncompress which will mean a significant slowdown of your computer.