Love the Aerosmith Version.
Still have an Alvin Lee version on cassette (God that is sad),...for the same song, and the one he did at Woodstock, which I forgot the title,..
Something like.....
Don't ask me what shape I'm in,
Can't sing, ain't pretty, and my legs are thin,..
"Don't ask me what I think of you,
I might not give the answer that you want me to." 
Alvin jammed for sure.
If I break out the Vanilla Fudge, you guys are doomed... 
The song you just described is "Oh well" by Fleetwood Mac. That was way back when Peter Green was still the leader.
Oh Well
Peter Green
I can't help about the shape I'm in
I can't sing, I ain't pretty and my legs are thin
But don't ask me what I think of you
I might not give the answer that you want me to
Oh well
Now, when I talked to God I knew he'd understand
He said, "Stick by my side and I'll be your guiding hand
But don't ask me what I think of you
I might not give the answer that you want me to"
Oh well
Performed by
Fleetwood Mac