Someone plz recommend the best games in DOS; any genre is ok, but looking for rpg/rts specially. Love master of orion 2 btw
Jazz Jackrabbit. An early game from Epic Megagames (now just Epic, creators of the Unreal engine). Fast based side-scroller well worth your time and effort. Plus, it has a badass sequel.
RPGs: Ultima Underworld. System Shock. Fallout 1 and 2. Strife. Eye of the Beholder. Alphaman. Bad Blood (make sure you get feelies from replacementdocs). Wasteland. Solar Winds.
RTS: Command & Conquer. WarCraft 2. Z. DOS was right at the beginning of good RTS so there aren't many which still hold up today. Older classic slow-paced RTS include Dune 2, WarCraft 1, Blood and Magic, War Wind.
MOO2 is really more of a 4X strategy game than either RPG or RTS. You might want to look at Civilization, Colonization, Populous, Star Control, Starflight, Defender of the Crown, Transport Tycoon Deluxe, Burntime.
I have never played Heroes of Might and Magic or Master of Magic, but from what I understand of them you might like them.
I wonder if you'd be into the first Dune game? It's a unique hybrid of point-and-click adventure, RPG, and RTS. I sunk many hours into that game as a kid, and I still enjoy it as an adult.
Look over the RPG and Strategy genre pages on Abandonia.