itunes is 10.5 plus so you should be fine unless it's a sloppy hackintosh job. I think this forum will be more helpful in this case. http://www.insanelymac.com/forum/ by the way you need to research doing a duel boot this will help you allot! or even tri boot mac os - window 7 or xp anf linux can all be run on the same computer. also if you check the forum I listed you might be able to update the os
So what do you need to do again?
Update it to 4.0 or you want to restore your iphone to 3.1.3?
If you dont have your SHSHs for 3.1.3 firmware saved it wont let you restore to anything but the latest 4.0 that came out today.
No matter what itunes version you're using.
I took it he was trying to update to the latest Itunes 9.2 so he could install 4.0 but I could be wrong. I would wait till dev-team updates RedSn0w if I were you. if that's what you are talking about.