Matt Laur , Jan 26, 2010; 11:14 a.m.
First, I would be very, very careful with that rig. They are basically fires waiting to start, or portrait subjects waiting to be badly injured. Don't turn your back on those hot lights for a second, and be sure to sandbag those stands to avoid unpleasantness.
What you're asking (about placement) depends on the look you're after. Sure, try the brighter light as a key, and the less-bright one as fill. You might consider using your strobe off-camera, behind your subject, as a hair light ... but you'll need to gel it in order to get the color temperatures to match (since the hot lights will be much warmer-looking).
For some ideas about placing lights, and how they'll impact the look of the subject, check out any of the gazillion free online lighting tutorials (including this forum's huge archives, or free areas like this).