First thing you're gonna want to do is use some hard drive cloning software to clone your Windows 7 partition. Acronis True Image Home can do this for you and you can download a free trial from their website. Once you have it installed and setup (regardless of the type of cloning software at this point), create an image of your Windows 7 partition and have some sort of external media such as a external hard drive ready to offload the image onto, as it may be rather large. Also, make sure you make a Clone disk which you can boot off of to reapply your Windows 7 image. Acronis True Image Home has this option, as do other forms of cloning software
Next, as long as you know you REALLY want to get rid of that Factory Restore partition and the Vendor Tools partition, stick in an Ubuntu live cd and open up the partition manager (GParted) and delete the Restore partition and the Tools partition. At this point you should have some free space at the beginning and/or the end of the hard drive. Confirm that you are 100% sure you want to delete your installation of Windows 7, then nuke it.
After all this, create 2 new partitions in GParted: 1 Ext4 partition for Ubuntu, and 1 Swap partition for your swap file. Don't worry about Windows 7 at this point. Continue with the installation filling in your credentials.
Once you have Ubuntu booted, updates and all, reboot and boot off of the clone disk you made earlier, and reapply your Windows 7 image to the free space left over. Reboot and Voila, Dual boot Windows 7 and Ubuntu without having to reinstall Windows. You may run into the problem of having either of the bootloaders fail. If GRUB fails to load and Windows 7 boots on startup, their are tutorials out there on how to fix this, and vice versa on Windows 7 bootloader failure.