it may be a shame to lose them, but using a halogen light is bad just like said above....If your a beginner maybe you should try something simple first like CFL's or at least invest in a metal halide....If my plants ever stretch that bad I'd rip them up in a skinny minute....Trust me you'll be more unsatisfied trying to mess with it, then starting over and doing it right.....4 weeks of growth doing it right could have a bushy plant at the same height with multiple branches then a anorexic plant that looks like it's having trouble breathing.

So basically what I'm getting at is:

1.) Rip them up
2.) Do a little more research on lights and what kind for your setup
3.) Start over and do it again with hopefully better results!

Other than that, Good luck with w/e you decide to do!