I know it's going to be hard to pick just five, but give it a shot. I'll post mine now, and in no particular order, just the five that I think are the best from each decade:
1980's:
1 - Where The Streets Have No Name
2 - Bad
3 - I Will Follow
4 - All I Want Is You
5 - With or Without You
1990's:
1 - Mysterious Ways
2 - Lemon
3 - Please
4 - Ultraviolet (Light My Way)
5 - Mofo/The Fly
2000's:
1 - Moment of Surrender
2 - Beautiful Day
3 - Kite
4 - City of Blinding Lights
5 - Crazy Tonight
1980's:
1 - Where The Streets Have No Name
2 - Bad
3 - I Will Follow
4 - All I Want Is You
5 - With or Without You
1990's:
1 - Mysterious Ways
2 - Lemon
3 - Please
4 - Ultraviolet (Light My Way)
5 - Mofo/The Fly
2000's:
1 - Moment of Surrender
2 - Beautiful Day
3 - Kite
4 - City of Blinding Lights
5 - Crazy Tonight