I would hazard a guess that it's BitTorrent which is causing these false alarms (DOS MSDTC attempt - ID 1408), as I'm also running BT and I've seen these same IP notifications. If you're not forwarding port 3372 (listening port for the Microsoft Distributed Transaction Service Coordinator) from the external interface to a client on your LAN running MSDTC, you should be fine!
I would hazard a guess that it's BitTorrent which is causing these false alarms (DOS MSDTC attempt - ID 1408), as I'm also running BT and I've seen these same IP notifications. If you're not forwarding port 3372 (listening port for the Microsoft Distributed Transaction Service Coordinator) from the external interface to a client on your LAN running MSDTC, you should be fine!