As Vimeous says, there should be no problem with your PC reading the drive; the disk will already be formatted. The only situation where you might have problems is if your laptop ran a different OS to your desktop and the drive was formatted with a filesystem your desktop PC doesn't recgonise. If they were both running Windows, you should be fine
There are a few adapters available that allow you to plug any SATA / IDE device into a USB port, although
tbh I'm having difficulty finding an "in stock" listing for one at the minute (
here's an example at Play.com, though). These are great devices - I have one at work for doing exactly this job (recovering data from old PCs) and it does exactly what it says on the tin. It's well worth buying one if you can find one in stock anywhere.