Linux Mint Forums

I believe that the default is 5 seconds before booting the default entry in the grub menu. It is strange that yours is booting so quickly. You could try editing your menu.lst file. Typically, this file can be found in /boot/grub/.
Then use an editor to open menu.lst.
About a quarter of the way down the file you should see a timeout parameter (should be set to a default of 5). This value is in seconds. Change it to something longer and save the file. Reboot the machine. See if that helps you have enough time to boot into Vista.

If you have configured grub recently and your settings aren't default (and if the above doesn't help you) try posting the content of menu.lst here.

I hope this is what you're looking for.