As an FYI the following link explains how to create a bootable USB drive from the Snow Leopard media. I just followed them and can confirm it works on a late 2006 Macbook. Though I'm not sure how helpful this will be if you can't use either of your optical drives:
http://computers.tutsplus.com/tutor...e-usb-drive-with-os-x-snow-leopard--cms-21491
I tried that.
When I connected the external optical drive, it spun, and the Snow Leopard DVD briefly appeared on the left in Disk Utility, but then disappeared. It kept spinning, and DU stopped responding. I had to force quit, but when I relaunched it, it immediately froze again. This happened several times. I tried to eject the DVD, but then the whole machine completely froze. Even the dock froze- I usually keep it invisible, with the icons enlarging as they're moused over- it froze with some icons enlarged.
I restarted and tried again. This time nothing crashed, but the DVD just wouldn't stay in DU. It kept appearing for less than a second and then vanishing.
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I'm wondering if there's something wrong with my computer's ability to read OSX DVDs, like some piece of code that allows it to do that broke. Is that a thing that could happen?
If that's what it is, I'm wondering if I should buy Lion from Apple. $20 isn't so much to pay to get a functioning machine back. Then I could try putting Lion on a thumb drive and see if that works. If it does, then I could use it to do a clean install on a new SSD, and hopefully leave whatever demons are causing this behind.