Dunno how to even frame this question...
I used to have this issue earlier with CD-drives of yore.. where certain CDs couldn't be read by older drives (I think the discs were recorded with >8x speed). Now I'm seeing this issue with my trusty DVD drive (which has served me well for 2-3 years). It still can read DVDs that I burned as backup (in short it works) - however every now and then I get a DVD (usually ones that come bundled with tech magazines) that my drive doesn't 'see'. It freezes up for a while and then either it shows up blank or asks you to insert a DVD.
Usually I just take the DVD to my relatively newer work laptop and sure enough the DVDs are fine - so I copy then over to a USB drive and then back to my primary machine. This has been annoying me no end..