A lot of files are misnamed, often on purpose. It stinks. But there are things you can do:

Look up files with Bitzi before you download. Right click on file > advanced > look up file with Bitzi
http://www.gnutellaforums.com/showthread.php?t=37676

Within LW tools > options > filters > keywords. Here you can add specific words to filter out & also tick 'ignore adult content' & apply.

(To post a new thread, go into the section where you want to post & click on 'new thread'. Top left, below 'user CP')