QUOTE (dies @ Nov 10 2008, 04:22 PM)

Set the OS X partition to active using something like
http://downloads.partedmagic.com/the first one in the list or the gparted liveCD, download and burn it to a CD, boot from it, then you just open gparted, right click the OS X partition, choose manage flags, then set the boot flag on the partition. Now that partition will automatically be selected in the Darwin bootloader, then you can set the timeout to 1 if the other way won't work for you.
I'm sure there's other ways, but either of those CD's are very easy to use and really nice to have around.

Even though Darwin lists vista first does not mean it will boot it. It will boot from the partition you set it to boot from (can be done with the com.apple.Boot.plist flag rd=diskXsY, but should be checked manually first to make sure you don't get any kernel panics). Usually, even if osx is 2nd on the list and vista is first, it will boot to osx w/o any modifications (so it always happened on my installs of JaS distro). Just check it first, without pressing any key when you get to darwin, just wait for the timer to finish and see if it boots to osx. If it does, you can then play with your com.apple.Boot.plist file, and not making any changes to your vista install.
The other thing is that you're not making it very clear. What is your active partition? I'd also recommend what the above person said, marking your osx partition as active and using darwin as a main boot loader. You can get parted magic on a flash drive, which, in my optinion is more convenient than a CD. Instructions are here:
http://partedmagic.com/

(lol, it says " The Parted Magic website has been hacked. I'll try to get it back up as soon as possible."

)
Alternatively, you can do this to flag your partitions active:
- Insert your Mac OS X Installation Disc and reboot.
- When you get to the screen asking to hit "any key" or "F8", hit "F8" and type "-s" and hit enter.
- When you get to the prompt, type "fdisk -e /dev/rdisk0" and hit enter.
- Then type "flag x", where "x" is your osx partition number and hit enter.
- Then type "update" and hit enter.
- Then type "write" and hit enter.
- Then type "quit" and hit enter.
- Then type "reboot" and hit enter.