The other day I was spring cleaning and came across several old pc's; 2 still kicking and one with dead capacitors on the board. Of the survivors was an e-machine from '01 at most, and a Dell Optiplex 210L from '06. I cleaned them off, both the system and HDD for protection and decided on the Optiplex as the most usable. After some light research I found the possibility of upgrading on the Optiplex's pentium 4 with the LGA775 socket, but decided against spending money as I want this as a pure revival not a "million dollar man" project. Wanting some form of security I found the novelty of installing windows 10 home, on a system that can't run windows 7 to my knowledge. The problem with windows is the ram requirements for almost everything, so I turn to linux for an even more bare bones os to put less stress on this old horse. The endgame is to have it as an emulator for it to run retro games, other functionality is a plus. The system has a pentium 4(1 core), 1gig of ram, board has A02 BIOS, and only 76G of storage when unformatted. Being as this will be my first venture into linux, what would be the suggestion for a lightweight linux os that won't cripple the system when an emulator front like RetroArch is run? If it is an option could the emulator front like this be the sole os?