Rice is absolutely better than Williams. His problem has been staying healthy.
I don't this anything is absolute regarding either player being better. While Rice might be the better deep threat, but Williams would get the edge most every other category.
How did the offense look last year with our #2 WR as the #1 WR?
Not nearly as good as 2010 with that same WR as the #1 WR. I'm pretty sure the #1 WR wasn't the reason the offense sucked in 2011.