What does a restore do? Does it usually help? Will I lose anything? Does it remove updates like 4.0.1? And about how long does it take?
If you restore as new it will remove everything. It will leave your iPhone like it was when you first took it out of the box. If you restore to a backup, it will make it like it was the last time you backed up your iPhone...which (as CPMS said), won't necessarily solve any problems.
Why are you considering a reset?
Thinking it might help my data problem.. As I can have 1 or 2 bars of 3G signal but not be able to do anything on data. Then if I turn Airplane mode on and off it will find a new signal and allow me to do whatever I need.
Sounds like a trip to a Genius Bar may be in order. Hope you have a store close by.