I had windows vista on one partition, xp on another documents on another and programs on another.

When I installed ubuntu on a new partition it very kindly let me see all the other partitions and mount them as necessary. I would like all my ubuntu files, documents music downloads to go right on to the documents partition so when I back up that drive to an external I have it backs up the documents drive it has all the files I have created in vista or ubuntu. Eventually I want to leave windows completely but I would still want to store all the ubuntu files on the documents drive.

Now .. I can go to "places" and mount the documents drive but what I would like to do is when I fire up ubuntu that the documents drive mounts automatically.
Alex

they way i would do it is put in a custom command for mounting that drive like so more or less
mnt /dev/sda1 /mnt/documents (i know thats your main hdd but you get the idea)
in theory that should work im not compleatly sure though worth a try

There is no need to do it this way. Adding an entry to /etc/fstab should suffice. asumofparts, you'll want to look at the man pages for fstab and mount in order to do this.