MiniMax, i think there's a slight difference between FreeDOS and FreeBSD... (; I think it's totally possible to run DOSBox under FreeBSD (which is more or less a Unix flavour, like Linux - yes, i know the whole truth is a bit more complicated (; ).
siffland, DOSBox is quite CPU intensive, in general. The latest version (0.72) has brought a huge performance leap (with the dynamic core), but you'll still need a fast processor for good framerates (especially with action games). I'd say your processor will only be able to deliver a handful of FPS, but that's just a guess. It might be enough to play "slow" titles, but i highly doubt you will have much fun playing the games. The next problem would be the RAM. You'll need RAM for your OS, and for the emulated machine, of course. Your 192MB are just sufficient for the OS and some apps, i think.
In my opinion (and from my experience), you'll need at least something in the P4/2Ghz class with 512MB RAM for fluid play, and that's even with "slow" titles. I'm using DOSBox with a P4/2.6Ghz/1GB RAM, and i'm seeing occasional "hiccups" with "slow" games - demanding stuff, like Blood in 800x600 runs at unplayable framerates. The same machine is able to run modern 3D games, like STALKER oder C&C3 at stable framerates (with less-than-maximum-details, of course).
Bottom line: try it. "Playability" and "Fun" are measured on a subjective level, so your play experience might differ from mine (other other's).