I'm going to download Lubuntu 32-bit. But when tryig to download from http://lubuntu.net/, there's only lubuntu-10.10.iso
http://lubuntu.net/
lubuntu-10.10.iso
I don't know whether this is 32-bit or 64-bit
Version 10.10 original release is 32-bit.
Newer releases also support 64-bit.
Given the focus on resource-constrained (and older) computers, if there's only one, it would be 32-bit. It was when I downloaded a previous release some months back.