We've got a support subforum for software/hardware issues right
http://www.gamesas.com/index.php?/forum/126-fallout-new-vegas-dlc-hardware-and-software-issues/, which is where you might wanna direct issues like this in the future. ^_^
Are all of the current updates installed? And make sure you have your regions version for all of the DLC (pre-order bonuses aswell) as having conflicting regional DLC has caused me problems in the past. :brokencomputer: