I am running lw on a mac os 10.3.9. I never had a problem until yesterday. LW starts up fine then when the main screen comes up at the bottom it says "locating peers" with the little bar underneath that shows it's 'working'. When you try to click any key or go into the preferences, it locks up. I can still use other applications on my computer. I have also tried to erase and re-install LW, but this still happens.

Does anyone have any answers??

Whilst LW is closed, delete the LW preferences found here /Users/your_username/Library/Preferences/LimeWire
(BTW by deleting your LW prefs folder you will need to reset all your options next time you start LW.)

It would also probably be worth doing a safe boot & repairing permissions. ie: reboot whilst holding down the SHIFT key until you see a message saying SAFE Booting. Once it's started up, open Disk Utility found in your Utilities folder & repair permissions. Then reboot normally.