Yep, realy played the s**t out of HOI-2. Bought it in the "Doomsday" version and later upgraded to "Armageddon". Bought HOI-1 later from the bargain bin, but couldn´t get into it. The detailed research was nice, but ordering each division around (not being able to form corps/armies) killed it for me (Like, if you had to order each ship in Aurora individually)
I´d realy reccomend to go for HOI-2 over 1.
Note: The fixed date events are still there, but if you stray from the historical path, some (many?) won´t fire. Example: Anschluss in ´38 (Austria joining Germany) will not fire, if Germany is at war.
Furthermore, most events have a probability assigned, so while usually, after beating up France, they will sue for peace and Vichy will be created, there is a chance they fight on.
Of course, navel combat is, well, not exactly well done (Carriers are basicly battleships with VERY LONG RANGE guns), the AI does not play by the rules (unlimited range for ships, for example, which makes "Island hopping" irrelevant for the AI and establishing a defensive perimeter for you, if you are playing Japan, pretty much impossible) but overall, I liked it - a lot!
There are also quite a few good mods for HOI-2
If you want a more "realistic" game, have a look at the Stony Road mod, for example