I have a laptop with Windows 7. Sometime ago, I tried to install Ubuntu using the cd and clicking the option "Install with Windows", however it never worked, never finished the installation. Now I am trying to install it again. I know how to make partitions and format them using Linux Command Line, but only with "empty" drives. Now, I have lots of information in my HD. When I insert the CD, Ubuntu displays the message "Multiple Operating Systems detected" which leads to two options: "Erase everything and install Ubuntu" or "Use the partition manager", when I see the manager I only see two partitions, one is very small (sda1 like 512 Mb) and the big one (sd2 = 318 Gb). As far as I know, I would need to erase Ubuntu's bootloader. My question is, How can I install Ubuntu using "Install with Windows" options instead of manually making partitions?
You can use the wubi installer, which will let you install Ubuntu in and alongside Windows.
Wubi is an officially supported Ubuntu installer for Windows users. It can install and uninstall Ubuntu in the same way as any other Windows application. It's simple and safe.