Originally Posted by 37speed
I installed Windows 7 on the entire hard drive then installed Ubuntu. Ubuntu repartitioned the drive. If you partition it first then when you install ubuntu using the wizard to "install alongside windows", it only divides up the current partition Windows is installed on.
The easiest way to do this is to first install Windows to whatever size partition you want for Windows. Leave the rest of the drive unallocated.
Then install Ubuntu. Choose manual partitioning. Create 3 partitions for Ubuntu: root (where the OS lives), swap (this is analogous to virtual memory in Windows). The rest of the drive will be /home (where your data and user specific settings are stored).
This way if you ever reinstall Ubuntu all of your data is safe on a separate partition.
Root can be 10GB, or up to 20GB if you have the space.
Swap can be as little as 500MB-1GB if you have a lot of memory. If you plan to suspend to memory, then let swap be at least equal to the amount of physical memory you have.
The rest of the drive is /home.
See this site for some great dual booting tutorials: http://members.iinet.net/~herman546/