Well, U2 kind of was born in the same time as Joy Division. Of course, the success is totally different, so is the music..
U2's success contributed to let them experience new things in the early 90's with Zooropa and Passengers, to try to make a pop album with Pop, then they are back to their old selves in 2001.
So, what's your favorite album?
Should be a tough race between Joshuan Tree & Achtung Baby IMHO.. I think Achtung Baby will get my vote, because there is no bad tracks on that album, but I like Joshua Tree as well...!