Play & keep. I enjoy having the archive around, even if I'm not going to be actively using most of it save for a couple days a year. It's good for research (sometimes it's faster just to pull out my copies than to look things up online). Most importantly, it's especially good for sharing with others. I've had such times come up a lot over the years.
My brother to a friend 'No, Kid Icarus was great, you have to try it if you get a chance!"
Me overhearing: "I'll go get it set up."
Brother: "Wait, you HAVE Kid Icarus?!"
My sister: "I'd love to get that original Zelda collection for my Gamecube, but it's too expensive."
Me: "I have it if you want to borrow it."
Sister: "REALLY?!"
Friend: "Have you heard anything about this Journey game? It looks good & the soundtrack seems cool."
Me: "I have it- when can you come over?"
BIL: "I'm probably gonna get rid of my PS2 stuff soon, my only controller broke so I can't play it anymore."
Me: *Throws PS2 controller at him*
BIL: "I can't take your controller!"
Me: "It's fine, I've got 5 as it is. I'm sure I'll find another one cheap at a thrift store eventually anyway." (One week and $2 later I'd already replaced the one I gave him)
Going through the collection & relishing the nostalgia & the history is fine, but nothing- NOTHING- beats the sharing with others. Makes me wish I had more people to share with sometimes.