I was just in Froyo and my phone was beginning to lag and run kinda rough. I was weary of flashing because I dont know too much about it and I could afford losing the phone. However, I decided to factory reset (will lose info) and go for the One Click Odin to GB 2.3.5. I cant tell you how much I feel it improved my phone. It was very easy to do(Open Odin, Connect phone, click Start, Done!). Perhaps you can try factory resetting to see if your phone responds and if you feel like you want more, go for GB.