How to unlock and root my T-Mobile G2?

primesuspect

I'm going to Taiwan in a couple of months and I want to be able to buy a local data/phone SIM for the week. I guess I have to unlock my phone.

I found a guide that was a couple of years old; is there a current best-of-breed how-to and software package for my phone?

Since I'm rooting it and unlocking it anyway, I may as well ask about ROMs. What is the G2 capable of?

Thanks in advance.

Tushon

For cyanogenmod, the entire process from stock to "input custom ROM" is located here
EDITS:
A ton of possible options for ROMs (both ICS and Gingerbread-based) here (follow directions from first link until actually putting CM7 on your phone and pick another mod instead) located here
(of those, the most recommended in my limited experience are Cyanogenmod or MIUI)
Make sure to check what you may encounter as working/not working due to driver issues in various mods (FM Radio, for example)

A GPS patch which is really freaking cool here and can be used on almost any phone (he links to other builds as needed)

Thrax

All you need to do is SIM unlock your phone. Unlocking the bootloader and rooting won't do this for you. Call T-Mobile and let them know you're traveling, and they can unlock for you. Worst case, you pay ten bucks for a code.

_k

http://support.t-mobile.com/docs/DOC-1588

primesuspect

Thanks everyone