It's against the forum rules to ask for helping doing illegal things. And despite your desire to buy them, it's still illegal to download them.
That said, they were probably burned to the CDs in SVCD format, which isn't the same as just burning the files onto the disc. I dunno if there's a similar format for DVDs, but at the least you can create video DVDs out of them just like if you were converting your old VHS tapes to DVD. Google seach should be able to find solutions to this.