All I need to do is restore my iPhone through itunes so that I can return my iPhone to my service provider? Is that enough to un-jailbreak it? Anything else I need to do to cover my tracks?
Jailbreak or not, most people would probably restore before returning their product anyways. Do away with all the apps, contact information, etc. Why leave it there when you can wipe it off with 2 buttons?
If I was having problems with a non-JB iPhone then I would try restoring it before sending it in. It's a pretty standard troubleshooting step and shouldn't cause any sort of suspicion.