As for the "disagree" situation, I think the overused expression, "Agree to disagree" may be a viable alternative.
I disagree. ;-)
I think that there is a qualitative difference between mere disagreement and disagreement because of intellectually bankrupt positions.
1) Mere disagreement
"I do not feel that homosexuals should be allowed to marry because I think it is too devisive an issue right now."
"I do not think homosexuals should be allowed to live because their behavior is an abomination to nature and this can only lead to societal ruin."
"I disagree with that intellectually bankrupt position. Your argument employs only two fallacious premises with a naturalistic fallacy and a fallacious slippery slope argument."
In those examples someone might think that both positions are intellectually bakrupt. For example one might think teh first position is "stupid".
But ultimately there is a decided difference between teh two positions.
One is devoid of any substance and employs two logical fallacies to support the position. The other does not employ any fallacies.
So while I might disagree with the merits of the former it is a disagreement with an argument that is not intellectually bankrupt.
The second position is intellectually bankrupt.