Sony Vegas Pro 9.0 and Kodak Zi6 - HELP!

Hi,
I'm having a few issues with editing the .movs that come out of my Kodak Zi6. The files are 1280x720, 16:9, 29.97fps.
Here are the problems:

1) There's no audio.

2) The system LAGS LIKE CRAZY. Even when I minimize Vegas and then bring it up again, it takes about 2 minutes before I can do anything. Nothing else is running on my computer. I have 3 gigs of RAM.
2a) Every action takes forever, too. Even the smallest edit. I shudder to think what will happen when I start adding effects.

3) When I try and render a "preview in player" it tells me I don't have enough memory. I have about 40 gigs of space. I tried "setting the RAM to 0" as I saw in a forum, but it still didn't work.

Are these issues related?

You may have answered these questions already....

Thanks!
Brendan