Sounds like you might have to do a reset. It sometimes happens after an OTA. They try hard to avoid users having to do it, but sometimes it's the only answer.
Your pictures and stuff should already be on the SD card by default on the DInc2. If your contacts are Phone Contacts instead of Gmail contacts, you will want to back them up from the People App -> Menu -> Import/export -> Export to SD card.
Make a quick note of what apps you have that you really like, the market will remember any paid apps, but not the free one's. Also make a note of how your screens are set up. It will make setting up your phone again a lot easier.
Then under Menu -> Settings -> SD and phone storage you should see Factory reset.
This will clear all the data from the phone but not the SD card. When you reboot you will walk through the setup again and you can login with your Gmail account.
Sorry dude. It's a PITA, but in the long run it should be a better phone overall.