If I happened to have an old, 32-bit laptop laying around, what #Linux should I put there?

@heikkiket i suggest debian, just note that they might be dropping support for i386 in the future: https://www.phoronix.com/news/Debian-Plans-Cease-i386

but debian has a stable release schedule, so the current stable version (bookworm) will be supported until 2026, and then it will have long term support until 2028 so you don't really have to worry about it

Debian Likely Moving Away From i386 In The Near Future

There was recently a mini DebConf in Cambridge where the Debian GNU/Linux release team held a spring and figured out some items moving forward, including the dim future for i386 moving forward.