Runnig out of disk space???

My p.c is telling me it only has 8 gb of memory left out of the 70 gb it has on my harddrive.
Ive burnt all my files to disk and deleted any software i don't use but it still tells me the same.
Ive looked in my documents, my computer and IBM Preload and clicked show hidden files, but still i can't find any pictures or files that i have downloaded from the internet anyware.
I know that this is what is using up all my memory , because i've added the size off all the software up that i us and its only using less than 2 gb of disk space.

This is starting to get very frustrating as i can't use the space i need becauce its clogged up with rubbish.

Just wrote this on the off chance that someone here might know a lot more about computers than i do, and may be able to point me in the right direction.

I would very grateful for any kind of help anyone can give me thankyou.

try opening control panel and going to add/remove programs and check for anything that's big that you don't use and remove it. i hope that helps.

try to buy another hard drive. or try tu put new windows.

You should use the disk cleaner application in windows.You can do this by going to Programs>Accessories>System Tools>Disk Cleanup. If that doesnt work try to clear your internet browser cache by going to Tools> Internet Options> Delete files if you use IE and Pressing Ctrl+Shift+Delete if you use firefox.