I think what the OP is referring to is using linux for parallel processing in a cluster. http://www.linux.org/docs/ldp/howto/...g-HOWTO-1.html
If you have a decent internet connection, I would say just go out and get multiple distros on live cd. Pretty much every distribution has a live cd option now and that way you can test many different ones to see which one you like best, and which ones work with your hardware easily. I'd definitely check out Ubuntu, Mandriva, and Fedora to start. Of course, you'd be running the os off of a cd so the speed would take a big hit, but you'd be able to get an idea of how things work. You can also dual boot as noted, so you could keep windows and linux on the same system
Would 3 partitions be about right? the root partition on the first disk, the swap partition as the first partition on the second drive and the home partition as the second partition on the second drive?
is that sort of setup easy to astablish during an install?
Once you go to install, this should be simple enough to do. When you install, choose to manually partition. Delete all partitions on sda (or hda if you have older IDE hard drives) and create a single new partition, using all available space. Tell the installer that you want it to mount as /. Delete all partitions on sdb (or hdb) and create a new partition the size you want for swap, tell it to use as a swap space. Create another partition on sdb using the rest of the free space and tell the installer to mount as /home. Pretty simple.