I can only really comment on the last ten years as I’ve only been properly watching since 2001 (and even then I was only six!), but two of the most exciting all round races I’ve seen are Germany and Hungary this year. They both had long battles for the lead, with constant switching of places, and excitement all the way through the pack. Other non-2011 races which were great to watch are Suzuka 2005, Hungary 2006 and Brazil 2001 (one of my first F1 races I saw all the way through live), because they all had battles for the lead, different leaders, and excitement all the way through.
Maybe someone who’s been watching a bit longer can comment on races a bit earlier, because I only know about them from season review videos.