My internal space is all taken up and I can't move anything to my SD card, what can I do?

I just barely bought my HTC Desire phone about a few days ago. The internal storage was low. However, with only a few days passing, and only about three of my personal apps downloaded and I would hook it up to my computer for a charge, it would show that my internal storage is full and my SD card is practically empty. I deleted the apps that were preinstalled on my phone that I do not want. That did not even really help. So I tried to see if I could move my apps over to my SD card. It will not allow me to do so. Then I disabled some apps hoping that would do it as well. My internal storage is still fully taken up and I am not pleased with this problem at all. What can I do to get my internal storage back into the "blue zone and out of the "red zone"? Thank you.