shoot them with a single camera so that the file numbering is sequential (ie IMG1000, IMG1001, IMG1002, etc). Then open up quicktime and open an image sequence. Direct it to open the pictures you shot. Then export a QT movie in whatever codec you want to edit in. You can then use Compressor or FCP to adjust the speed of playback.
This is an overly simplified way to do it. If you had After Effects, I'd suggest using that.