I should add Disk Cleanup done, didn't help much.
Ignore my joke name, have long ago upgraded from Vista to Windows 7 which I love.
Am approaching the limit of my C drive and encountering system instability and can't seem to make enough space. About a month ago I moved videos, audios and photos to my almost-empty E drive which freed a lot of space on C. But since then the space has been filled again even though I haven't installed new programs or stored any video/audio/photo, making me wonder if something I'm unaware of is creating the problem, such as some kind of backing up that I'm unaware of, especially as there were at least two crashes. I also ran a virus check on AVG which brings up nothing.
So I installed and ran Wiztree which identifies fat files and folders, which might indicate where I can delete. The biggest file at 23.4 GB is of course Windows - is there anything in that file I can safely delete?