Originally Posted by Geo411m
Well, rooting your phone allows you to have administrator access to your phone and thus due thing not normally possible on standard android. With it you can have all your apps and caches run from your SD card, apply themes, tether your phone, enable auto rotation and the list goes on. Here's a few links of interest to help you get the most out of your rooted phone.
complaments to the android community forums for the answer to this
o and depends on what you want to customize.
there are theme packs. different roms. different versions of the core and so on and soforth
http://geekfor.me/ has my favorite rom the FRESH rom. but to use these you have to root your phone. and before you ask how do u do it
http://forum.ppcgeeks.com/showthread.php?t=90380 has all the answers. thank thacountry for that. btw he rocks