IMO, there are only Two Types of Files that are Relatively Safe to download from the Gnutella Network.
These would be mp3's and AVI's.
Any Program, Game, Zip or Rar Files along with WMA's and maybe ?? .Mov files are Extremly Dangerous.
When I was using LW I actually Filtered these File Extensions. .wma, .exe, .rar, .html, .com, .zip, and .mov, Just to be as safe as possible.
There are other options other than the GN for downloading said files that are much safer.