My detailed analysis:
1 - MI2. A quest for four map pieces to the greatest treasure of all time that leads you into the clutches of your worst enemy. Lots of background story too.
2 - MI3. Similar to that of MI1 but with more background story.
3 - MI1. Typical story. Villain steals your love interest, you set out to save her, showdown with villain, with a twist at the end.
4 - MI4. Uhh. Something to do with tourists and a land developer with a bad Australian accent.
1 - MI3. It's not 3D but it looks so much better than MI4. Beautiful hand-drawn backgrounds and characters. By far the most good-looking game of all time. I'm judging these by how good they look by the way, not resolution or anything like that.
2 - MI2. Hand drawn also but low resolution. Had almost as good atmosphere as MI3.
3 - MI4. The background were nice but the characters stuck out horribly off the backgrounds. And the character models weren't much to look at. But to be fair, it was better than in MI1
4 - MI1. Well, as far as graphics go it's not much to look at. I think it was done on paint.
1 - MI3. WOWEE! What can I say? It's the best soundtrack of any game ever. It draws you into the game and the sounds make you feel like you're there. Great ambience but with a strong tune and great adventure music.
2 - MI2. Some very good original tunes. Woodtick was especially good. My favourite was the music in Largo's room.
3 - MI4. This was pretty good. But had bad tunes as well as good. At least it had music running through the entire game. The ambience was annoying though and drew from the environment.
4 - MI1. Some good tunes but there were only a couple and a few were irritating.
1 - MI2. I thought it was a great ending. I didn't find it too confusing. It was like how a book ends and says "But it was all a dream... or was it?" I don't know of any other games that did this. Probably one of the most controversial endings too.
2 - MI4. I don't know about everyone else but I liked the "Herman is Marley" idea. Not very well explained but for me, a very satisfying ending.
3 - MI1 and MI3. I liked them both and they were pretty similar. Both had a romantic ending.
1 - MI2. Some bits were a little harsh but oh so funny. The 'bust' jokes at the Elaine's place. And the Phatt island guard.
2 - MI3. Very close between 2 and 3. I loved the barbershop quartet tryouts. And swindling a budding young entrepeneur.
3 - MI1. Most of the humor was in the characters and conflicts. Insult swordfighting was great.
4 - MI4. The jokes were either lude or smothered with corn. Did like the jokes about the Jambalaya waitress.
Overall, MI2 wins, followed by MI3 then MI1 then MI4.