you should be able to use that key with anohter copy of Vista. however im not entirely sure how it works with Vista.
With XP, it had to be the same edition e.g Pro or home, also it had to be either pre Service PAck 2c or Post Service 2c disk as they changed the COAs.
If it came with the computer any OEM or VLK licensed disk should work. If its a retail copy then you need retail disk.
If it came with the computer as a restore disk you can reobtain them from the manufacturer with Acer for my laptop cost £50.
If its a standard OEM or retail disk ~Microsoft should replace it for a small charge even for the OEM media kit is about £22.
I might be totally wrong, as i say Vista is still fairly new in corporate sectors which my experience lays