Drag it to the Trash, do a Spotlight search for lime, drag results to the Trash, search for gnut, drag to the Trash. LimeWire is evil, and badly written. If you must use a P2P app (and most of them are evil, but some were created less evil then others), then Azeurus seems quite highly commended 'round here. I'd help you more, but I steer clear of the P2P stuff. It's 'orrible. 🙁
It keeps everything in the RAM yet still manages to be constantly writing to your hard drive. It messes with port settings and can down a wireless network in minutes. LimeWire is evil. It should have been made by Microsoft.