If you have all your items saved to your computer with Active Sync, then do a master reset:
HTC Touch hard reset
14 January 2008
- Power on.
- Press and hold buttons marked 1.
- Press and release 2 with stylus.
- Release buttons marked 1 when menu comes up.
- Press directly down on center dpad, marked 3.
You can also get tips & tricks from www.htcwiki.com
It has the latest and great updates, software, even known issues if you ever come across this. HTC does recommend that you do a master/hard reset once a quarter to keep it moving smoothly. Also, ensure you don't have a lot of open running programs. Perhaps once a day, clean the cashe and history. Do a soft reset (aka battery pull) once or twice a week. All depends on how hard you play with this lovely PDA device!