The second idea is a good one!

You can pull out the hard disk from the old laptop and put it in the new laptop, but it may not work -- OS, specially the newer OS like Vista, are very picky on hardware. Most of the time you have to re-install the OS. The second idea is a good one. Get an external disk enclosure and put the old drive in. You have a new laptop and a "new" removable hard disk now.

Good luck!