I had a pc with windows vista on and then got a new laptop so i installed ubuntu onto the vista pc using the USB installer (i didnt really know what i was doing just messing about i dont know a lot about this stuff however im competent with computers and such, enough knowhow to build a pc). Since then for some reason windows has become corrupted and wont launch so i cant go in to delete the files to clear up space as there is very little space left. Is there a way i can do this through ubuntu?

Edit: Its dual boot as it gives me the option to choose but the vista one doesnt actually work for some reason, system restores and fixes failing.
I cant see any of the files for the vista side from within ubuntu to delete them in the first place.