For years now it seems like every third DVD I write turns out bad.
I write to disk successfully but when trying to retrieve data back to hard drive
Windows hangs.

I got to wondering if there is a gig limit as to how much Win 10 can pull from a DVD in a single transfer
and if breaking, say, a 4 gig file into multiple one gig rars might solve my issue?

Its more likely your DVD drive might be on its last legs.

Optical backup made sense in the past - but in this day and age not so much. Perhaps if you do it on Blu-Rays, but even then retrieval is less than ideal and some disks can just die outright.

You're much better off getting two large capacity hard drives and either use them in RAID or keep them in sync with each other for redundancy.

As to issues with Windows and DVDs, I'm not aware of there being any. What are you using to burn them?

Good advice, dvds are not a great idea for storage now. Games can spread over multiple (even Blu-ray) discs. Hard drives are so much cheaper and easier to use. You don’t even need massive ones if you look at a raid setup, I have several terramaster d5-300 boxes, and have 4 or 5 5tb or 6tb in for massive storage, and raid 5 to allow one drive to fail at a time. Sure, you need also proper backups, hence why I have three of those, and some other external ones, but depending on your storage needs you could have multiple drives coalesced in one box, or a raid driver card in you main machine with a stack of drives.