Patience is a virtue, especially when requesting help from volunteers!
And "bumps" only take up space on this forum; they don't ring anyone's bell.

The search results wherein your search is echoed back to you with something added on is simply a spam generator. After seeing my search results always including "...has orgasm on webcam", I simply added 'orgasm' to my filter. (When it's an mp3, I imagine one can only listen to said webcam orgasm).

You did the right thing. Files in your Shared (downloads) folder that you did not request should be deleted. I don't know what's in them, (perhaps they really are data and backup files); I'm not gonna look.

If you're dl'ing only mp3s and AVIs, then any strange files that come with them really are strange (delete them).

If you download torrents you may see strange files that actually belong there. (If you're downloading only via the LW search results you're not doing torrents; don't worry about it.) If you are doing torrents, stop torturing yourself with LW (use uTorrent or Azureus).

Getting Started Using LimeWire - Gnutella Forums is chock full of good info.