If you've never heard of a codec-pak then that's good. Chances are you didn't install one and you don't want to install one. Still it's very odd that your Vegas Pro 10 cannot edit AVCHD files from the HD PVR and mine can. Something about your PC is conflicting with Vegas and making this not work.
What is the resolution of the MP4 file you are recording? (1280x720? 1920x1080?)
What are your project settings (Press Alt+ENTER to see)
Can you post a screenshot of what you are seeing so that we can see too?
~jr
http://www.johnrofrano.com
http://www.vasst.com
