No matter how you cut it, there isn't much security available in P2P networking. While a blacklist may prevent you from connecting to known IPs, the record companies, movie companies and others you're attempting to avoid with the blacklists have countless other IPs that aren't blacklisted and also contract third party companies.
With BitTorrent you're connecting to other anonymous members making it easy for anyone to see who is downloading a specific file. One of the jobs I did from time to time when I worked for Time Warner Cable years ago was process abuse complaints. The RIAA, MPAA or whoever connects to a torrent file just like anyone else downloading the same file and they can see all the IP addresses downloading and seeding it. They then take those IPs, send them off to their ISPs who simply plugin the IP and time and date into a tool that spits back the customer information which they send back to the request issuer (MPAA or whoever) who then send their cease and desist order or file a lawsuit.
Bottom line is, if you're worried about security or doing something you think may not be totally legal, BitTorrent is not a smart move even if you are using a private tracker with encryption and a blacklist.