I've looked at some tutorials about removing drive partitions and seen SOME suggestion that you can really foul things up if you don't know what you're doing.
The only reason this should concern you is if you have important data. You say you don't (bookmarks are easily saved to a usb flash drive or even floppy if your box has one), so no worries! I agree 100% with custangro, wait for mint9, when it's released, backup your bookmarks, wipe the whole drive clean, and let mint do its thing during install. Should be fairly painless, but if you have troubles, post back, and we'll do our best to help.