Buying the Correct Enclosure
The idea of a drive enclosure seems simple. Find an enclosure, pop in the drive, and you're done. Simple, right? Well, not so fast. External drive enclosures differ from each other in a few important ways.
Build quality is one important difference, and it can vary greatly. The two most popular materials to build external drive enclosures out of are plastic and aluminum, and of the two the aluminum is usually the better option. It is just as light, it conducts more heat away from the hard drive, and it is not prone to cracking or fading in the same was as plastic.
Features also make a large difference, with the most important features generally being the inclusion of a fan and the option of hot-swapping. A fan is not a must-have for keeping a drive cool, but it isn't a bad thing to have. Noise should not be an issue because the sound of the drive spinning will easily drown out the noise of a fan. Hot-swapping is a feature that allows drive to be removed from the enclosure while the enclosure is on. It effectively makes any drive in the enclosure a Plug-and-Play drive. This is a must-have.
The last and most important trait to consider is the type of connection the enclosure uses. USB 2.0, Firewire, and eSATA (three way comparison here) are all popular methods for connecting an enclosure. Some drives offer multiple methods, but they also generally cost more. Any of the connection methods should be suitable, but I recommend eSATA (provided of course the computer it will be attached to has an eSATA port) as it provides the highest bandwidth.