I hard deleted them from Dolphin.
I have no idea what kind of data test drive put in that partition; all I had was a ~1GB dd image file and the other 198+ GB is magically allocated.
The only way I was able to recover my system was by disabling Secure boot, loading up the Mint 15 CD and deleting my backup file (6GB). I deleted the dd image file left in the /home folder (somewhere in which I had selected to use as a temp repository the first time I tried) and after a dozen reboots and a file system check, the rest of the space automatically freed itself.
Somehow, and I am uncertain how, test drive managed to do the same thing to my root partition, causing another fun crash.
Needless to say, that program no longer resides in my OS.
I am using my tablet at work at the moment, so I can't give you the exact commands used.