I just downloaded Limewire basic, to try it out, and it says I am connected, but at won't let me download anything - there is a gold bar at the top of the page with a lock on it what do I do?

What happens when you try to download? Do files move into the download pane? If they don't, try the advice here.
License (click)

If files do move into the download pane, but just sit connecting for ages & then get stuck needing sources then you're probably seeing fake files. Check out the threads below for info & tips (use Bitzi to check files before download).

Fake files showing up in search results
How to find music

The orange warning banner with the padlock was added because there's a bogus LW update showing up in search results. It's a 75.7 KB .exe & shows up as "Urgent LimeWire update - download & install now". If people download that thing they could end up infected. To try to prevent people from downloading a dangerous file, the warning banner was added to LW's interface.
The padlock symbol doesn't apply to music, movies etc...just to LW updates