NESticle X.XX is your best bet. It hasn't been updated since 1998, but it has good compatibility and many features. It's still the premier in NES emulation on DOS-based systems. System requirements are very meager as well, needing only an 80486 processor and 8Mb of RAM.
ZSNES was my emulator of choice for MANY years back when DOS was still a thing, even though I think I've always used the Windows versions. As far as I can tell, the DOS version is still "up to date", too: https://zsnes.com/index.php?page=files
I thought there was a DOS build of SNES9x (which is my current SNES emulator of choice) but a quick search didn't turn up any recent download links.
Comments
http://www.emulator-zone.com/doc.php/nes/nesticle.html
http://zsnes.com/index.php?page=files
http://www.snes9x.com/downloads.php
go to zophar.net find a dos version.
ZSNES was my emulator of choice for MANY years back when DOS was still a thing, even though I think I've always used the Windows versions. As far as I can tell, the DOS version is still "up to date", too:
https://zsnes.com/index.php?page=files
I thought there was a DOS build of SNES9x (which is my current SNES emulator of choice) but a quick search didn't turn up any recent download links.