Hi, Scelzi41. You posted this in the Photoshop Elements forum and very few of us use Premiere Elements, which has its own forum. It's better to ask PRE questions there, since you'll get better help. I'll move this over there for you.
Probably the easiest way to do this is to Share/Publish+Share each Project to a separate file, then Import those into a "master Project," for authoring to a BD.
I agree with Bill. Output each finished video using Publish & Share/Computer/AVCHD with the preset for M2T 1920x1080i 30. These segments will then load perfectly in an AVCHD project.
I am not sure what your plans are for a disc menu for this grand project (5 projects in one), but I would remind you that "Premiere Elements (any version) Blu-ray disc format on Blu-ray disc" playback does not recognize stop markers.