I read the Mars series and the Tarzan series by Edgar Rice Burroughs when I was a teenager and loved them all. Remember that they were written in a different time (ie. man strong, woman weak and must be rescued, good is always honourable etc etc). But for uncomplicated adventure they are wonderful.
I read A Princess of Mars, and really, it wasn't all that bad, but I just couldn't finish it. Not the least of which reasons was that I had better books checked out (which reminds me, I have to turn in these overdue books I never got around to reading. Curse you only-24-hours-in-a-day!) I could deal with the language, I could even deal with the insane feats of strength and the sketchy science. I couldn't stand John Carter though. He's kind of a dick. And I mean, it wasn't even because of the whole Man strong, woman weak thing. Hell, if I recall, the Princess of Barsoom was strong and Amazonian. Book smelled good though. I may not read as much as I should, but man I love the smell of an old, old book. The paper is all woody, uh, it's like a cabin built in the middle of the forest of manliness and libraries. but yeah, not that bad of a book. Didn't seem like there'd be much character development and the Carter seemed kind of like a Mary Sue...