G1 Unable to get past android boot logo
Have you tried doing a factory reset (you'll lose all data)?

Steps to do a factory reset are found here.


1. Power off the G1
2. Hold Home Key + End key for 20 
seconds or until you see a "triangle with an exclamation point
and a picture of the G1"
3. Open the QWERTY keyboard and hit Alt+W
4. Restored!