>>17143
Well, bare in mind both series have been dead for anyplace that's not Japan for years, so I might be outdated in my suggestions. Likely the new games coming out will be easier to get into. Anyway, with Nobunaga's Ambition, the PS2 games are very easy to get into. Overall I find it more difficult to master than ROTK, oddly enough, though both series are very comparable. Those PS2 games should also have ports for PC, but I know they have PSN versions. Get those if you can. Iron Triangle or Rise to Power are both really similar, doesn't matter.
As for ROTK, that's a different matter. I-VI they kept to a standard format of controlling a county/kingdom etc., but IIRC 7, 8, and 11 all feature a more expansion system that enables you to create characters and play them, or pick any officer to play. This ranges from someone like Liu Bei, to being a general with Xiahou Dun, a tactician/diplomat like Zhuge Liang or Zhou Yu, or start off a a ronin type and wander between different provinces, building up stats. Personally, this is my favorite system in the ROTK series because it's easy to learn if you start off as just a ronin or a basic soldier. You can then work your way up of course.
1-6, 10, and 12 I think are all more focused on governing and gameplay from the top, like Nobunaga's Ambition. I don't know how 13 will be, if it's that simpler style like 10 and 12, or the complex 'roleplaying' system they had in 11. Maybe a mixture of both. Anyway, try out 12. If not, same for ROTK. I recommend the PS2 era games. There's a few ports to the PC for them, and they're also on PSN. I know for a fact ROTK 12 is on pirate bay right now.