This might be a "last resort", but compressing large files can free up a tiny bit of space.
For example, if you get the program 7zip, you could zip up some files you don't use as often to free up disk space.
However, you might have to unzip the files when accessing them, that might be annoying, but if there are any files that you don't use but want to keep, I would recommend compressing them with a program such as 7zip or WinRar.