hmmm... its an ISO file. Try to use Nero or other program (MagicISo, PowerISO) to open it and burn it. DO NOT burn it directly to the dvd, otherwise u'll just end tranferring it to the DVD. If all else fails, mounti t with Daemon Tools and burn an exact copy from the virtual drive to your dvd burner.
BTW, vista RC2 JUST (like 10 minutes ago, for the x64 version, 3 hours or so for x86) came online. If your a CPP member, which I assume you are, grab ithere before MS takes it off.
damn, i was experiencing cookie probs with IE7 on vista build 5728 so sorry i couldnt reply earlier... I've got RC2 running now and its fine.
Can you pinpoint what exactly is the problem? I recall having a problem where I would mount the Vista RC1 ISO file and it would display a single text file telling me something about a udf code or something...
I'm assuming thats the problem you have. I don't remember exactly how I fixed it, but I think opening the file with PowerISO or MagicISO should allow you to read the full contents of the ISO, as well as burn them.