Don, try a hard reset by following the steps from here first"

1. Turn the power off. If your HTC Aria is frozen, pull the battery out and reinsert it

2. Hold the Volume Down button

3. Hold the Power button until the display turns on

4. You are now presented with a menu that allows for Fastbook, Recovery, Clear Storage, and Simlock

5. Select Clear Storage by pressing the Volume Down button

6. Press and release the Power button to select

7. Confirm: Volume Up for YES and Volume Down for NO"

This will delete all the data from the phone, but not from the memory card.

If that does not help, you might be due for a digitizer replacement. The video instructions are available here and you can get the digitizer from places like this. Hope this helps, good luck.