I am attempting to install Ubuntu 12.04 side by side with Windows XP SP3 on an old Dell Dimension 2400 and the LiveCD does not give me the option to install them side by side. It only gives me the option to either delete Windadd device to boot sequence dell dimension 2400 windows xpows and install Ubuntu or "do something else." I am unsure of how to set this up. I also don't understand why the default option to install side by side is not available.
UPDATE: I booted into the LiveCD using the "Try Ubuntu" option and attempted to resize the NTFS partition with GParted, and was informed the drive has bad sectors. It told me to run chkdsk /f /r from Windows and reboot twice and then I will be able to resize the NTFS partition. I have also taken a look at the Windows Dual Boot link provided by the commenter below, but I am unsure what is specifically meant by the line "Create a Partition for your Ubuntu installation."
In regards to the comment "perhaps there is not enough Hard Drive space for dual boot," the computer in question has a 75GB hard drive.