1. Is it possible to get the custom rom back to the original and lock the gps and radio and EVERYTHING back to the way they were before i did it?
YES...
2. When i flash it will it erase everything on my sd card and my contacts and stuff like that?
It doesn't touch your SD card, but you are doing a hard reset so it will erase your contacts. Its a PDA though back them up.
3. Is it easy to do?
Depends on your comfort level, its pretty easy for me
4. What are the risks?
You could brick your phone and render the warranty useless.
5. i would also like to have all the windows mobile stuff like the text conversation and the the office mobile.
Thats all built into Windows Mobile, you're not converting it to Palm OS or anything?
6. What is the best rom for all this stuff?
The best ROM for a Verizon TP to Enable the GPS (Sorry TP doesn't have an FM Radio with Verizon) is SCROSLER Rom, see my sig for the link. Check his thread for instructions and details. His ROM gives you more free memory, and makes the phone a heck of a lot faster than it is stock.