I suppose with all the bland characters on this show, it's only to be expected that Steve Urkel would eventually take over the show. But did they really need to turn to all the completely lame and pathetic scientific crap to keep the show fresh? By scientific, I mean the machine in Urkel's basement that turned him into the ultra-suave Stephon Urquell. Of course, he used this alter ego to swoon Laura, the woman of his dreams. However, for a show that was supposed to be about good old family values and a family trying to make it by in the 'hood of south Chicago, this seems a little far fetched. It isn't the freaking Jetsons or Lost in Space!
That aside, the show wasn't very funny at all. Every good sitcom has at least one character who is in the spotlight and is usually the center of most of the hijinks. This show didn't have that for me, as I found Urkel to be extremely grating and one dimensional. His signature "Did I do that?" got old after one season, but he was never given anything else to work with.
In summation, I don't recommend this show and I don't think it's any small wonder why it is hardly shown in syndication anymore.