Originally Posted by TentativeChaos
Ok, so I booted from the CD now I'm installing it and I chose a custom install because I want to partition the hard drive so that Vista isn't deleted. How do I do that?
That depends on what you already did to get the partitions into the strange condition shown in that picture. Try providing more info when asking a question.
Maybe an expert here can deduce a lot from the hint that the partitioning program can't determine the Used amount on your larger ntfs partition. I can't.
Maybe you used Vista to shrink your C: partition to around 10Gb and to create a D: partition in the free space, and then you didn't finish initializing the D: partition of about 300Gb (which is fine because you didn't really want it created at all).
If that is all true then the first step in the Linux partitioning tool is to delete the partition in /dev/sda3. However, if there is some other reason you have two ntfs partitions, and you have data in the big one, then you don't want to touch it in Linux until you do something (probably shrink it) in Vista.
Once you have free space, from deleting a bad ntfs partition if Vista created one, or from correctly shrinking an ntfs partition, then you want to create (in a Linux partitioning tool) the two or three partitions needed for Linux.
I've seen some recent threads discussing how big those should be, but I haven't seen any clear answers. It depends on your intended use. But you probably can't get a good answer from that either. If most of that 300Gb is available, you can afford to make the root partition bigger than you need and make the swap partition bigger than you need and still have most of the space (also likely more than you need) available for a /home partition.
For the actual mechanics of deleting and creating partitions, I'm not sure the partitioning program you're using in Ubuntu is the same as the one I just used in Mepis, but try this and see. IIRC, I was was able to start each action by right clicking on the line in the partition list and selecting the desired action from the context menu: Right click on the garbage partition (IF THAT IS WHAT IT IS) and select delete. Right click on the empty space that creates and select create a new partition and tell it how much space to take (do that for root and for swap then home, taking all the remaining space for home).