noeyephone

Greetings,
I broke the LCD while replacing the digitizer on my HTC Mytouch 4G, and I didn't factory reset the phone before the procedure. Now I have a buyer for the phone. Is it possible to reset the phone with only stripes showing on the display?
-or-
If I change my Gmail password on my desktop, will this prevent the buyer from accessing my email account (and app store, etc) after he repairs the unit? I hadn't ever checked email on it, but did enter my Gmail login/pass to access the free Google apps. I can't remember if I ever hit a "sync" button, so is there a possibility that all my emails could still be in a cache?

Thanks for any help. These forums are a lifesaver.
RJ