Rooting and installing/flashing a ROM to your phone will open a whole new book of functionality to your D2G. I am currently running a rooted D2G with the Liberty 2.0 ROM. It is certianly something I do not regret, but I cannot stress enough, you MUST read before you do anything. You are tampering with the system framework, and something can go wrong. You wanna be very familiar with how to do whatever you're about to do, and how to use RSD Lite, so when/if you do brick your phone, you can fix it. You can PM me if you have any specific questions reguarding rooting your D2G.
As for cases, I have found almost all sliding stlye droid phones have rubbish cases that break. I wouldn't waste the money, and just get good insurance on your phone.
