Mount & Blade Collection
Before you buy...
If you only want to buy one of these, get Warband and Napoleonic Wars mod for Warband. No one really plays Fire and Sword because in my opinion, you can get mods for free for Warband and Fire and sword really was not that great at all. A lot of multiplayer servers shutdown for Fire&Sword. Warband is the ultimate Mount&Blade multiplayer game. The first one is great too, but it's not multiplayer; however, it has mods that Warband does not have like the Star Wars mod.
On that note, you also will want a Steam account regardless where you're buying this because you need it for joining Regiments and clans. I have played a server on Napoleonic Wars recently with 170 people on a public server. Warband itself has a lot of players still. as of Dec. 19, 2012.
Proves graphics don't matter
Let me start by saying, these games cost 60 dollars in total. Look at the price up there. These 3 games are amazing and should be tried by all. Please, give it a chance.