I had the same 3G problem after updating to 2.2 along with a few other issues. After doing a Factory Reset all my problems went away. Not sure about saving your contacts to your SIM card. I haven't ever tried that.
I had tlost 3G problem before the upgrade to 2.2 so I did the upgrade hoping to restore it. No luck. I tried a lot of different things but I deleted the APN and added the exact same information, I was able to get 3G back.