I am thinking seriously about installing Ubuntu 7.10 on my HP dv1000.(1G memory)
However, I am wary of doing anything to disrupt the linux partition already on the harddisk(for the QuickPlay of DVDs). How would I go about finding out exactly which partition is being used for the QuickPlay option? Am also Considering Suse 10.1. Which distro is best?

Hopefully that's a Gig ...
My new Dell XPS has a media playing partition - type x'dd'. Never tried it.
Just ignore it. I never use the normal CD to install Ubuntu - I prefer the "alternate" as it gives better control of the partitioner. Used to be the "normal" CD was bloody near useless for partitioning - I stopped using it around Dapper timeframe probably.
On the Dell, all the disk space was used, as was all the primary partition slots (the media partition was a logical). So I just shrunk the NTFS and shifted the extended/logical down and installed into some of the (now) free space. Gparted did it all fine.