In the future, you should backup your data. you should get an external hd enclosure. An hd can crash at any time. Five years is a good life for an hd.
I recommend you do a google search on any external harddrive you are looking at.
I bought a low cost external drive enclosure. When I started having trouble with it, I did a google search and found a lot of complaints about the drive enclosure. I ended up buying a new drive enclosure. On my second go around, I decided to buy a drive enclosure with a good history of working with Macs. The chip set seems to be the key ingredient. The Oxford line of chips seems to be good. I got the Oxford 911.
I'd give OWC a call. 1-815-338-8685.
FireWire 800 + USB 3, + eSATA
&
save a little money interface:
FireWire 400 + USB 2.0
This web page lists both external harddrive types. You may need to scroll to the right to see both.
http://eshop.macsales.com/shop/firewire/1394/USB/EliteAL/eSATA_FW800_FW400_USB
(2) FireWire 800/400 Ports (Up to 100MB/s / 50MB/s)
(1) USB 3.0 Port (Up to 500MB/s / 60MB/s)
(1) eSATA Port (Up to 300MB/s)
Has a combo firewire 800/400 port. Not sure what this is. Looks like you will need 400 cable.
http://eshop.macsales.com/shop/ministack
Backup software
Use apple's Time Machine
Carbon Copy Cloner will copy your startup drive to an external firewire drive. You can boot from the external drive to verify that you have a good clone. When you upgrade your existing startup drive, you can at any time boot from your external drive and go back to your existing system.
http://www.bombich.com/software/ccc.html
SuperDuper is the wildly acclaimed program that makes recovery painless, because it makes creating a fully bootable backup painless. Its incredibly clear, friendly interface is understandable, easy to use, and SuperDuper's built-in scheduler makes it trivial to back up automatically. And it runs beautifully on both Intel and Power PC Macs!
Give SuperDuper a workout on your own system. Clone to your heart's content — for free. See what else is possible. When you're convinced that SuperDuper is a terrific solution — and a great value at $27.95 — you can register right from the application and start using its advanced features immediately!
http://www.shirt-pocket.com/SuperDuper/SuperDuperDescription.html