lurking for a while....finally signed up. lil help?

[killswitch]

So...this is probably in the wrong forum but I couldnt figure out which one to post under. Please move to the right one if need be.
Ok. I recently bought an htc evo on craiglist that turns out to have a bad esn
It is also updated with the most recent 4.24.651.1. So I cant root yet.
I have decided that for the time being I would just like to use it as a Media device. Maybe play some games on it from the app store, use the wifi for surfing...maybe skype ect.... use it as a gps without cell service if thats possible. It has been hard reset, but when I go to the phone setting it still has another persons email and phone number in the about phone section. How can I erase this and set it up with my own google account so i can use the app store ect.
Thanks for any help.
Thanks
Killswitch