LimeWire is legal--you don't download from LimeWire but from others who share their files. If you use LW to download material that the laws of your state and country say you shouldn't, then you can get in trouble. Since LimeWire connects to the Gnutella network and has many international users, the laws on what is or isn't legal to share vary greatly.

If you are in the US, see http://www.eff.com/share/

btw--you inadvertently (I hope) insulted anyone who might try to answer you by assuming they would lie and that you are someone they should obey.