Since Windows uses empty space as "swap file space" and you have VERY little, you will definitely have problems running this, and it will be terribly slow and inefficient until fixed.
WinDirStat is a terrific free/shareware utility that I recommend you find and download. It searches your entire drive, and organizes a listing from "most space used" to least. It also produces a visual map of that space. You can click on a chunk in the image to see what it is, too. I find it VERY helpful in identify what to clean up. One thing to be aware of is that you can't delete everything "extra" at once. Once you've deleted 2-3 GB, stop and empty the Recycle bin, and then continue, gradually increasing the amount you delete. You can leave WinDirStat up, and it can re-assess regularly.
Here's a screen shot of how the results look:
WinDirStat.png (429.93K)
Number of downloads: 11
DuplicateFileFinder is also helpful, but more of a chore to work with at the outset. I'd start with WinDirStat. Hope this helps!
p.s. Your Recovery disk is fine; I recommend you DON'T touch it at the moment.