No clue where this belongs, possibly under harware, but Shrink Forum has always been of help to me on past issues.

I use Verbatim DVD+R to archive videos. Many require significant compression due to being TV Series on DVD. I use AnyDVD to rip and Shrink to compress (and burn via piggybacked Nero). I have quite a few DVDRs burned, some of which I've had a couple years and some that may be years before I get around to watching. This has raised my curiosity about the lifespan of recordings to DVDR and what factors are at play.

Does compression affect lifespan any? Does Shrink compression vs other compression programs make a difference. Crap media vs good and having a good burner I would think would be the two most influential factors (aside from maybe safe storage). I'm concerned that I may have DVDs going bad before I can even get to watching them or that I will have to burn them again before too long.

Can anyone advise about DVDR longevity for me? Thanks.

What's important for a good lifespan is the dye used in making of the disc.

All my Verbatim +4x are still holding strong.Occasionally I have to re-rip from them. Major issues,then they'd Crc out during the rip. Re-ripping your backups are also an effective way to test out your backups. Re-rip them back onto your hd. Dvd decrypter and ImgBurn only takes 5 mins or so to rip a properly sized backup onto the HD. Then delete the files when you are done.

Compression: Mainly playback is what's mainly affected. You will see slight blockiness. Max Smoothness and Max Sharp helps a lot,but you can see a difference. Over time,should still look pretty good.

To help the lifespan:High quality Advanced Metal AZO dye of Verbatim and Tiayo yuden. Burn half the rated speed. Keep the discs in a vertical position,dry,and out of the sunlight. There not going to last the 100+ yrs that they thought they would.I'm also keeping all my VHS and 8MM tapes safely stored because they will last longer than dvd media.

A good quality burner also helps immensely. That's why I am highly fond with the near extinct Benq 1620-1650- RIP Ben Q! There's some crap burners out there. I know because I have 1 HP and got rid of a pc of Crap I/O Magic 16x.

4+ yrs ago, I transferred all my VHS and 8mm tapes onto dvd using my TV recorder. Ruined 1 recorder after 2 weeks. Took a month to back up everything and I used whatever media that came with the recorder(cyberhome),Sony +4x,Verbatim,and Memorex +4x.

Before the holidays,the Ex Wife wanted copies of those discs. The cyberhome backups were plumb full of errors,and unrippable. The sony D04 re-ripped with no trouble.Same with the Verb MCC-002 and Memorex Ricohs. I gave her the home vids that ripped,but I have to go back to the tapes and redo everything that was on the crap media, UGGH!!!.

Yeah, shrinking isn't literally compressing it. It's still 1s and 0s that are recorded to media so it has no effect on archivability. Media quality and storage are the most important factors.
I have 5-year old Verbatim and Ritek DVD burns that are still problem-free, although non-important data I burned on Philips 2.4X DVDs became unreadable after a year. Of course no one has the time to check every disc they burn, so it's a time-saver if you just buy the good stuff. You can run tests on your oldest discs too to see if they are still readable. A simple test would be to just copy your old DVD movie burns to your PC (since the copy-protect has already been removed, no need to re-rip - just copy). If you get CRC errors or if your DVD drive struggles to read the DVD, then you know your disc is going bad. Just watching the movie for skips doesn't really help because DVD players will just skip over errors which might not be perceptible to the eye. It's only when you have a bunch of errors that you have skips and freezing.