Have you tried using the junk filter (do not yell at me for suggesting this)? You mentioned the trash button, but didn't say whether you'd used that at length or not. It takes some training, but it's not totally worthless.

Also, try adding The TechNutopia Fullsize Hostiles List for BearShare and LimeWire

You can add it to FW. Place the list within FW's preferences folder (C:\Documents and Settings\your username\Application Data\FrostWire). Remember to show hidden files & folders, as the Application Data folder's hidden by default.