Hi, hangingkayaker. PRE has its own forum, and it's best to ask PRE questions there since few of us here use it. I'll move this over there for you, since you'll get more answers there.
There may be more elegant solutions. But, cutting and pasting (or inserting) from one project to another seems to be awkward in PrE11.
My solution to that would be to open a project you have where you like the beginning and ending. Do a "Save as..." naming the project "Template". Now cut out everything between the beginning and ending. Save again. You now have the a project named template you can open anytime. It will be more "tidy" if you keep everything related in the same folder.
When you want to do another video with the same beginning and ending, open "Template.prg" Immediately "Save as.." with a new name. Slide the ending out to the right if you are in Expert and build your video between the beginning and end. If in Quick, put the new clips between the existing beginning and ending clips.
I use two slightly different workflows, depending on what I have, and what I want to do.
The first, is just as Bill defines, where I have a "template," with my Intro and Outro, and just populate the area between those, with my new Clips.
I also have several "stock" Intros, and Outros, that I have created. As most of my current Projects are still SD (Standard Def), I have Exported/Shared the Intro as a DV-AVI file, and the same for my Outro. In my case, the first is named " ____ Intro" (I have several, that differ by the subject), and then "The End," which is usually more common, though I have three versions of "The End." For those, I just Import those two output files, as Assets, to be used as the first, and the last, in the New Project.
Similar, but slightly different. For one set of Projects, I had 17 slightly different versions of Intros, though the Outros were common. I used the "template" workflow, as I needed to customize each of the 17 Projects, but did not want to "start over," and using that template worked well, as I could tweak, as needed 17x. As I was authoring those to DVD-Video in Encore, I also created a "template" Project there, and all I had to do was adjust my Menus for each, then Import my unique Clips as Encore Timelines, ending with my The End Outro. Most of the "dirty work" had been done in the template Project, and I just did a Save_As for each, from "Disc_01" through Disc_17," making the changes necessary. Worked a treat.