I'll be honest, I can probably ask this question somewhere else but I'm already on GiantBomb, and thus we can all understand the lazy. 
 
Anyway, so I've got a JailBroken iPhone and this thing crashes on me at least 7 times a day. I want to restore it back to a vanilla-flavoured Apple firmware and then jailbreak it again at a later date (when they can get it working on 4.3 3GS). I really need to keep my contacts, messages, photos and notes. My photos and notes I've copied over just in case, and contacts have been synced to Google but I really can't trust that thing.  Any of you guys know what the best way to go about this is? Just a straight up iTunes iOS 4.3 download and install? 

Don't you just plug it into your computer and then choose to look for a new update for the firmware?