Hard Drive Dock - Recommend suitable internal 500Gig Drive?

Maximum budget about $80.

I want to add a hard Drive Dock (for easy plug-n-play) Backup of my 'audio files' which is about one album worth (16 songs) roughly about 95.Gig maximum.

The Hard Drive Dock I'm considering is; Thermaltake BlacX N0028USU (USB.2, 480 Mbps Max) $30.00

I like the idea of the Dock, because I don't want to add more clutter inside my PC and add possible heat issues, and I want to make it really easy to swap, plug-n-play without opening up the PC case.

.  Can someone recommend a good internal 500Gig hard drive (Primarily for Backup), no more than $50,?  one that is suitable for the Hard Drive Dock (Thermaltake BlacX N0028USU)

I'm a solo music artist/composer, once all 16 songs (audio recordings/mastering) is done I want to back that up and move onto Video Editing (6 Videos maximum) on possibly a clean slate using the existing Audio Drive hard drive.

I already have another C: [Programs]  Hard Drive where all my programs are installed.

I also want to back up the O/S and settings 'on the same new backup hard drive', will I need to create a partition to do that and if so, how would that be done using the suggested setup?

The reason why I'm thinking of going this route is; (1) Internal drives are cheaper, (2) Internal heat? since I'll be using the H/Drive Dock that should not be an issue, and since heat won't be an issue this might help prolong the life of the hard/drive. (3) Swappable, very easy Plug-n-play setup using the H/Drive Dock.

Thanks Scott, appreciate your reply :)

I slept on it, woke up and thought dang it, I'm going to get an external h/drive instead, something solid (well built)!

The Hard Drive Dock I'm considering is; Thermaltake BlacX N0028USU (USB.2, 480 Mbps Max) $30.00

 
FWIW, For backup purposes, I'd consider using a HD dock that has both eSATA and USB.
I use a pair of docks here for shuffling data.  Works great...
 
For the HD, a Samsung F3 500GB unit is hard to beat.
If you catch them on sale, you can get the 1TB model for as low as $55.
 

Casual analysis of online reviews for Seagate 500 GB quickly shows the contrast between the advantages and disadvantages, with users or love or hate them-and sometimes for the same model in the same review.