Without knowing your computer specs it's difficult to advise. Post information about your computer, Processor, RAM, Graphics, Make, Model, etc. Otherwise I suggest you go here http://windows.microsoft.com/en-us/windows-8/upgrade-assistant-download-online-faq and download/run the Windows 8 Upgrade Assistant. If your system passes mustard for Win 8 it may be able to run Win 10.
You could alternatively run the Win 7 Upgrade Assistant. https://www.microsoft.com/en-us/download/details.aspx?id=20 If that goes well you could purchase/install [yes, they're still available] a copy of Win 7 & get the free W10 upgrade being offered by MS. Microsoft will continue security updates for Windows 7 until Jan.14, 2020. Personally, my own opinion FWIW, I wouldn't run Win 10 on old equipment. Others here may post otherwise.
You can also check your computer's website manufacturer's support section as you can find out if newer Operating Systems are supported for your system.
my CD/DVD drives are super old and dont work properly.
Is your computer as old or older than those CD/DVD drives? Optical drives are dirt cheap these days. If you purchase, determine first if the drive is SATA or IDE. If your motherboard supports SATA then purchase that.
can I just move all my C drive files to my D drive
Yes, you can move pictures, music, videos, documents etc. You can not move any installed software. Those would have to be reinstalled. You would have to check those for compatibility with the newer OS. Also, lots of older hardware such as printers, scanners, etc may no longer be supported. You would need to check for drivers from the manufacturer's support page for those items.
Lastly, your computer is probably a good candidate for a LINUX OS.
Stay tuned, more advice is sure to follow.