What is using my harddisk space?

Sleep and hibernate are perfected in Win7 and modern features which should be tried, as you can walk away from your computer without worrying about going back to save work - for an hour or two (Sleeps) or for a day or more (Hibernates).

I keep all of my installs at defaults plus Hibernate at 1 hour.

Your disk usage seems normal. You want lots of Restore points to have maximum Recovery options, to the extent that I'd apportion more disk space (20%) for them: System Protection - Change Disk Space Usage

I recommend using the full features of Win7 without being penny-wise and pound-foolish. A larger hard drive is smarter IMO than turning off modern features.

Just my 2 cents.

Don't know how many programs I have installed, not too many but some large ones and I'm using 58.9GB after cleanup and system restore disabled. My Windows folder is 23.6GB alone (don't know whats been installed in there).
Only my programs, windows, drivers and maybe less than 500MB personal files are on my system drive (no games).

I also agree with gregrocker (post #11), although I don't use hibernation I do have it enabled, but I have only temporarily shut down System Restore for the purpose of checking the drive usage and will create a restore point when I turn it back on after writing this. This has saved many people and many people regret not having it switched on.

Duzzy, the minimum that Microsoft recommend for Windows 7 64-bit is 20 GB so at 23.6 GB I'd say yours is normal depending on what extras you've installed, such as language packs and SP1.

Yer, I'm not concerned I have a number of programs/updates I assumed would have installed a number of things in the Windows folder (eg. .Net Framework 4, VS Studio 2010 probably). It is also SP1.