On recent distros, I've found MX (mxlinux.org) to be quite responsive. They are now also experimenting with FluxBox ( https://mxlinux.org/blog/mx-fluxbox-2-0-settings-now-availab... ) and that really makes it quite snappy as it is very light on resources.

Another distro I like is "Linux Mint Debian Edition" ( https://linuxmint.com/download_lmde.php ) that feels more "light-weight" than its Ubuntu derived counterpart Linux Mint.