My self-imposed parameters:
1. One song from each band (hence prohibiting Led Zeppelin and Bob Marley from dominating the entire Top Twenty)
2. Take no historical consideration, just present day enjoyment.
3. They must rock...
Also, notice that I said my "favorite" songs of all-time, not the "best" songs of all time:
Danzig - Mother
Led Zeppelin - Stairway to Heaven
Pearl Jam - Jeremy
Weezer - My Name is Jonas
Ozzy Osbourne - Crazy Train
Bad Religion - Dearly Beloved/Sorrow (Alright, I'm cheating here a little but I found a clip with them together)
Pink Floyd - Comfortably Numb
The Clash - London Calling
The Smith's - There is a light that never goes out
Bob Marley - Redemption Song