Is there a way I could have a Dual Boot OS with the same OS? I want Debian, but I want Jessie, and Wheezy. Are they the same OS or are they different?
Yes you can dual boot with the same OS, same distro, same distro version. The different partitions do not need to know about each other, although it is customary (at least when disc space was at a premium) to share swap space when dual booting.
The only thing when using the same version of a particular distro (e.g. two times Wheezy), is that it becomes less easy to keep apart the different entries in the grub startup menu.