Let's see... not sure about top 5, these are just some that I enjoy:
1. Linkin Park - Yes, I know, but I enjoy their music, not because I find it "deep" or anything, just enjoyable. And that includes both their new and old stuff, so there. (Favorite Song: tough call, but I'm going with "No More Sorrow" for the time being.
2. Dave Matthews Band - this group is actually one of my dad's favorites, and soon became one of mine. (Favorite Song: "Everyday", gives me the good vibes, y'know?)
3. Gorillaz - Another long time favorite, for both the music and character backstories. (Favorite Song: "Feel Good Inc.", natch)
4. The Protomen - a kickass rock opera based on the Megaman games? What's not to like? (Favorite Song: Probably "The Will of One", if I had to pick from their first album)
5. Weird Al Yankovic - What can I say? I love a bit of fun parody songs. (Favorite Song: "Eeeevvvverything you know is wrong, white is black, up is down and short is long, and everything you thought was so important doesn't matter...")
There are more, these are just off the top of my head.