There are several ways you can use it. First you can actually stick it inside your computer so you won't need an enclosure. All you would have to do is to pickup a SATA cable (like this one
), then format the drive and use it as a backup drive. Or you can buy an enclosure and leave it outside the computer. Or lastly you can get one of these
and connect the harddrive to a USB port with no enclosure.
For someone that is not doing a lot with the computers, I would suggest putting it inside the computer.
But anyway you do it, all you have to do is format the harddrive (possible you would have to do a low level format) and then start using it.
Think about it. I can help you with any method you decide, I have used and still use all three methods. There is one thing that might go wrong, and that is if the harddrive is so messed up that it cannot be reformatted for whatever reason. If you stick the drive into the computer then you will be out some time and 7 bucks or so.