At the moment I'm only asking this question out of curiosity, so it's all hypothetical for now, but here we go. As I have a number of machines to play around with it stands to reason they don't all need to be set up to do the same tasks.
Let's say I was to have one machine that was only to be used for a few basic tasks i.e. playing music files, viewing pictures, watching occasional short video clips (music videos and family stuff, longest is about 11 minutes), and typing letters. Maybe an odd game such as Aisleriot Solitaire. NO BROWSER, machine not even connected to internet. Anyone under the age of 30 can be excused for thinking that computers don't work if they're not connected to the internet.
What would be the oldest Puppy I could still use, and how low resources could I get away with? I would still want comfortable usage, not a struggle. I can think of some quite sensible reasons for keeping some of these tasks completely separate from my internet browsing. Not least of which is interruptions (I think they're officially called "notifications").