IF you have a bench capper, you could give it a go. If you have one of the wing cappers, I wouldn't do it. Also, check to make sure the bottles you have are thick enough glass. It's been posted before about twisties having thinner rims.
Personnally, if you were given the bottles, and you have enough to otherwise bottle your batch (or time to get more pop top bottles) I would simply send them to the recycle center.