Hey Ridicully, here is Emily's response from way-back when that likely got lost in the mail: "Hi Ridicully,
One main difference between the first launch and subsequent launches is that the first time you launch, you don't have any save games. On later launches, you do. I'm wondering if something about the saved games (even just the auto save) for Ice Station Santa is causing problems.
The fact that you're using Vista 64 makes me wonder if this is a user account issue - we've noticed some weirdness with Vista 64 administrator and limited user accounts not behaving the same way they do in other versions of Vista and XP.
A few things to try:
Go to My Documents / Telltale Games / Sam & Max - Ice Station Santa. In this folder, you should see files ending in .save, one of which is the auto save. Try moving this to a different directory and see if the game will start now.
Try disabling UAC in your control panel. I'm not a Vista user so I'm not exactly sure how to do this, but these instructions might help:
http://www.vista4beginners.com/How-to-disable-UAC
Let me know if you have any success after trying these things..."