I have the O.G. white WiiU from launch, and I quickly ran through the 8GB hard drive space included, however, since hooking up an external hard drive, the system seems to crash and freeze a LOT. To the point where I have to force a power down almost every time I use it. Could my drive be shot?

I wouldn't say shot, possibly too slow. Do you know the speed of your drive? Most external drives are just 5400 rpm laptop drives, extremely slow. If your able, try hooking up a different drive. Typically the larger external drives are desktop based and they run 7200 rpm mostly. If your drive is an SSD based one I would look to your drive enclosure. The only reason I am shooting at the drive atm is because it is the easiest and cheapest thing to replace if needed. I also have a wii u, when putting apps/games on the external drive I had the wii u would sometimes just "lose" those apps so I had to put them back on the wii u hdd as the external hdd just wasn't able to keep up with the onboard flash memory. Since then i've hooked up an ssd to it with an enclosure i bought off of amazon and have had no problems yet.