For the most part, you can probably find the hogs with "df -h" (to list all your disks), "du -s" (to summarize disk usage at a particular directory on the disk). It's usually pretty easy to home in on the
source of the problem.
On Windows, there's a great tool called "Windirstat".
As it happens, "Windirstat" existed on Linux, first. I'd encourage you to try it: