Here's how I do it:
       1. Put the long clip on the timeline
       2. From the start move through it
       3. At the wanted In-Point hit CTRL I
       4. Move on to the wanted out point
       5. Hit CTRL D
       6. loop to step 2
       For me the most efficient way and quick.
       MaJo

This ends up with only your "wanted clips" all on the timeline in chronilogical
 order. The trick is that every time you hit CTRL-I, it omits everything in the
 timeline from the last separation point up to the CTRL-I

Auto add your default transitions, render and your done with a section of video.
 You'll have to adjust individual clip sound levels before you create a avi file.