Reddit reviews Generic SATA/PATA/IDE Drive to USB 2.0 Adapter Converter Cable for 2.5/3.5 Inch Hard Drive/5 inch Optical Drive with External AC Power Adapter

You may not have to do that. Pick up a SATA to usb connection.

Like this

Hook the bad hard drive to that and then to another computer. You can read the file structure and pull data off. Expect to pay above a thousand dollars to recover the data through a company.

I measure my hard drive and its actually 4 inches wide, would this product off of amazon work with mine?

https://www.amazon.com/dp/B01J7MWD4M/ref=sxbs_sxwds-stvp_2?pf_rd_m=ATVPDKIKX0DER&pf_rd_p=3524122362&pd_rd_wg=8ZQq8&pf_rd_r=73AR7B3K7Z3HG1W5X27H&pf_rd_s=desktop-sx-bottom-slot&pf_rd_t=301&pd_rd_i=B01J7MWD4M&pd_rd_w=vi3lG&pf_rd_i=hard+drive+to+usb+adapter&pd_rd_r=2b6a58c1-325c-46c1-a8a0-54a3932810f2&ie=UTF8&qid=1521149996&sr=2

You can use a USB adapter like this:

https://www.amazon.com/Generic-Adapter-Converter-Optical-External/dp/B01J7MWD4M/ref=sr_1_9?ie=UTF8&qid=1500639108&sr=8-9&keywords=ide+sata+to+usb

Edit: This one comes with an external power supply.

Any SSD will be an upgrade. I believe the late 08 can go to 8gb of RAM, if it can, I'd do that with the SSD, you'll extend it a few years easily, though you're stuck at El Cap, I believe.

480 GB SSD for 130
https://www.amazon.com/SanDisk-240GB-SDSSDA-240G-G26-Newest-Version/dp/B01F9G46Q8/ref=sr_1_8?ie=UTF8&qid=1491107037&sr=8-8&keywords=480gb%2Bssd&th=1

Screwdriver kit (if you don't have one, you'll need a Phillips #0 and a Torx T5 or 6 for the hard drive nubbins, skip if you have one!) for 15
https://www.amazon.com/gp/product/B015F734P0/ref=crt_ewc_img_dp_1?ie=UTF8&psc=1&smid=A13PRKMVKLJGWH

IDE/SATA to USB (if you want to copy data from old HDD to the SSD. Ignore if you want to start fresh) for 11.
https://www.amazon.com/Generic-Adapter-Converter-Optical-External/dp/B01J7MWD4M/ref=sr_1_18?s=electronics&ie=UTF8&qid=1491107469&sr=1-18&keywords=ide+sata+to+usb

There's a possibility the external enclosure is broken but the drive is fine (I've seen this quite a few times). Take it out of the enclosure and try to access the drive directly. If you have a desktop just plug it in as an additional hard drive.

If you only have a desktop you'll need a SATA (assuming this drive isn't ancient - left is IDE right is SATA http://static.diffen.com/uploadz/1/17/SATA-IDE.jpg) adapter to USB. If it's a smaller (2.5" drive) you can probably get away with something like this https://www.amazon.com/StarTech-SATA-Drive-Adapter-Cable/dp/B00HJZJI84/ If it's a larger 3.5" drive you'll want something with a separate power source, like this https://www.amazon.com/Generic-Adapter-Converter-Optical-External/dp/B01J7MWD4M/ I personally would err on the side of getting the external power adapter myself, to rule out "not enough power" as a reason the drive doesn't work.

edit: I would actually spring for something like this https://www.amazon.com/Sabrent-External-Docking-Station-DS-UBLK/dp/B00IKAQ538/ Only $23 but has a lot of good reviews, I've heard good things about it specifically in the past as well. The last thing you want to do is cheap out on the adapter and think your drive is dead when your adapter is really just crap.

If the drive itself works but the computer doesn't recognize the partitions, try using linux to DD the files over and then mount the partition manually. DM me if you get here and I can either give you some pointers (if you're comfortable with linux CLI) or we may be able to work something out.

If the drive doesn't spin up when you apply power you are dealing with a situation in which you can either accept defeat or pay a LOT of money to have the files recovered professionally.