MARRIED WITH CHILDREN, without a doubt, was more popular and had a bigger impact on pop culture than MITM.
I believe, along with THE SIMPSONS, MARRIED was one of Fox's first TV shows and the audience was broader. It set the tone of the Fox network. The writing on MARRIED may have been lowbrow, but it's funny how MARRIED was criticized then, when its humor was really similar to THE SIMPSONS.
I think MITM's humor was more in the post-FREAKS/GEEKS era. Who knows how it would have evolved if it had gone on for a few more seasons!