My cousin and I just finished watching Rome, all 22 episodes. What a spectacular show on a grand scale...they strove for authenticity in everything, and it showed.
KoH: Director's Cut is much better than the version they play on cable tv...makes much more sense and flows better.
13th Warrior: great movie in my book, same with Knight's Tale...they're just good swashbuckling style movies.
Might I also recommend, pre-medieval:
Spartacus: Blood and Sand
Spartacus: Gods of the Arena (prequel)
If you liked the movie 300, you're gonna love this show. The kill shots are freakin AWESOME, and the fighting is suitably visceral.