Yes, Civ is exactly the kind of game in which in hour 48 of what would be a 70 hour game, you realize you made a crucial mistake in hour 12 that cannot be fixed and which basically lost you the game. I hate that too.
However, from what I understand, you can adjust the game speed, as well as a whole host of other things, like how long you spend in each age, map size, etc., that can make the games playable in a single night or two or three hours. I've got my Civ 4 coming in the mail, and I'm sure I'm going to work it so that most of my games by far can be played in one or two nights at most. The 70 hour games are just too brutally punishing even if you win.
You should check out some of the civ boards. I've been looking one over that was linked here by someone earlier(thanks, Someone!), and it has people asking the same question and getting lots of answers several times a day. The community there was pretty strong before the game even came out because the board handled Civ's 1 through 3 already.
http://forums.civfanatics.com/forumdisplay.php?f=144
I think people are saying that a good way to start is to play on Noble level, which gives neither you nor the computer any advantages and isn't too hard, and you can play on a map like Chieftain, which I'm not sure is the quickest, but usually gives you enough space to build a bit before being overwhelmed by other civ's.
There's also an excellent walk-through Someone linked earlier, but it looks like it's down or something, so I can only give you the page I was on from last night, not the home page, and dunno if either of us will be able to access it fully again (hope so, this is one slick and cool walk-through):
http://www.kalikokottage.com/civ3/su...v4_walk_2.html