not the sort of thing you ever really know how well it works since when it's working you don't see/know/hear anything. Seems by far to be the most popular.
Hmmm for P2P applications apps like PeerBlock and PeerGuardian is effective but it is n't foolproof there is still that 1% chance they could find you . But they do work. So don't compromise PeerBlock and keep your lists up to date everytime you start it up
Private torrents are normal torrents the major diff being they are tracked by private trackers. The best option though is to go through a newsserver. There are many threads out there that explain all this stuff If you need some links pointing you to those threads just shout. Though don't go begging for invites unless you've been around for 5 or 6 months and have a 1000 posts many have tried and failed. But happy surfing