What version of Premiere Elements are you using and on what computer operating system is it running?
For now I will generalize the principles involved. If more details needed then, please supply the details of your situation and Timeline track placement.
You would place the gray tabs of the WorkArea Bar to span just the area to be exported.
The tabs are set...
Move the Timeline Indicator to the start of the segment, hold down the Alt key of the computer main keyboard as you hit the left bracket key [
Move the Timeline Indicator to the end of the segment, hold down the Alt key of the computer main keyboard as you hit the right bracket key ]
The critical step is to make sure that you have a check mark next to the "Share Work Area Bar Only" option in the export dialog (if the dialog has that option).
Please review and remember that the answers are in the details.
Oh, so sorry not to include those details, I write in so infrequently! I am using Elements v.11, on a PC with Win XP (upgrading after this project, but I could install and use Win 7 or Vista, I run all three on different computers).
Thank you. I have seen reference to a workarea bar, but had been unable to find explicit information about it. I know how to use set points, but didn't know how to use the alt  to define an area, or how to extract it after defining it. I will proceed to try this all out!!
Thank you ever so very much!
This was so easy, I was instantly successful. Thank you for taking the time to point out these simple steps. You saved me so much time!
That was great news of your success with the feature.
Thanks for the follow up. Much appreciated.