My Documents folder problem

I noticed recently that certain pages within internet explorer were opening as if I had chosen the "without frames " option, for instance yahoo mail. I am using IE7. I was going bto simply restore back to a point before this was hapening, but when i clicked on system restore it told me it had been suspended due to lack of space!...on investigation my computer showed my hard disk to be completely full (80GB). I looked through the folder and My Documents is showing at 29GB used space. However, I then went through all the folders and added up the space used and it came to something like 2GB...and I have clicked the show hidden files option. Am I missing something? Is it possible there are other hidden files on there that I can't see, either operating system type of put on by others? (this is a family computer and so everyone has access to it).
Thanks for your help

 

Using Vista?

http://forums.majorgeeks.com/showthread.php?t=137616&highlight=Vista+system+restore+points

 

Hi, no i'm using Windows XP SP2

 

Have you downloaded

all Windows updates? rolleyes

 

Try running a chkdsk. Sometimes your hard drive kinda screws up and it reports the free space incorrectly. You can do that through My Computer->right click C:->Properties->Tools->Error Checking, or you can type in run

chkdsk c: /f

The /f tells it to fix errors. This way is for if you want to do it the next time you boot up.

 

My Computer > Properties > System Restore tab
Check how much disk space you have selected, there is a slider bar Min. to Max.

 

Thanks everyone for the replies, the chkdsk sorted it!!