Besides, you can always delete something, not all, from Vista if you can't find the best way.
Frankly, you should find back disk for your photos and files. If you do have another disk, copy your file out from drive C, and format it.
OK, here is another thing. If you format C: not from within windows, you may not be able to restart your vista because some boot sector in C: is needed to link your vista.
If I were you, I will copy files out, re-partition the disk and re-install vista.