Backing up files from corrupt disk from Windows Bootcamp
The solution is MacDrive, you'll be able to download a trial version for 5 days that should be enough to grab everything you need before formatting! Download it, install it on your windows partition, restart your computer, access Windows once again, open MacDrive and from there you can access your MacHD partition, if it's corrupt it will tempt you to fix it, you might as well try to, you never know, but if things don't go the way you wanted well just open the disk and try to reach for your most desired files! Copy them on a hard-drive and you are set to wipe everything! Of course if you really appreciate the software you might as well buy it! Good luck!