I decided to restore my iPhone in trying to get different features when I re-jailbroke it on redsnow. I restored it, then went through the paces in order to jailbreak it again. When I got to the part about it preparing to jailbreak, after the options screen, it freezes and I have to cancel, then restart my iPhone. It was not jailbroken when I restarted it. I have tried it five times now, and it's getting really annoying looking at that black homescreen instead of a wallpaper behind it.
If you are using a Windows PC. You might need to right click on the redsnow executable and choose run as administrator and then try it that way. I recall having to do that before, but I can't remember if it was redsnow or snowbreeze. But either way it should work.