I had a lot of fun with machines equipped with low end hard drives at a time when 40MB seemed like a big deal compared with 20. The old Mac Plus, the first 9" B&W classic. Of course, its users were normally well content with an 800kB floppy drive, but the former owner had lashed out on a 20MB external hard drive whose audible chattering betrayed its good humour and continuing health. I believe it was powered mainly by clockwork, but it also had a SCSI controller, oldie stylie 50 PIN cables, and a military-grade steel case of generous proportions and massive weight, and a hardworking fan. The sound it made as it booted from off was lovely: like a miniature knife-grinding museum starting up at 11am for Visitors' Hour. But hey! If it's worked this long, it'll probably work a bit longer. I'd advise techniques that use the absolute minimum of violence on the hardware. And once you've got the data backed up and reformatted for the modern reader, think of all the fun you can have if you network up that machine and use it as a webserver for a couple of novels or something.