I would start here:
http://forum.ppcgeeks.com/moto-droid/
At the top you will see 3 stickied threads:
http://forum.ppcgeeks.com/moto-droid...ions-here.html
http://forum.ppcgeeks.com/moto-droid...op-5-apps.html
http://forum.ppcgeeks.com/moto-droid...our-droid.html
The third one where you need to start. Once you root your phone you will be able to do all sorts of things, including flash a new custom ROM that should get rid of all your freezing issues.
Above all you need to read, read and then read some more. Don't dive into anything until you have educated yourself on how everything works.