At almost four and-a-half hours, if you start early they’ll carry you through to lunch! If you get up late I guess you can watch the first movie then break for a bite; afterward the second film will take you through to tea.
If in the evening you want to play them out, I recommend either Howard Whitehouse’s Science vs Pluck or Bjorn Reichel and Christian Steimel’s Triumph & Tragedy Colonial Supplement. Daniel Mersey’s The Men Who Would Be Kings is another fun game.
And goto Major General Tremorden Reddering’s Colonial-era Wargames Page. Trust me. [Here’s another link. I don’t know which is better.]