Re: If you were starting the Steelers from scratch and could keep only ONE player...
If we are talking about players in their prime, then I'd go with Casey Hampton as a cornerstone to build the rest of the defense around.
If we're talking about players now...holy crap. Your best players are getting up there in years (Ward, Smith, Hampton), have had injury problems (Troy in particular) or may be a product of significant talent around them (Holmes has Ward, Parker, Ben, the LB's have a great 3-4 DL with good LBs around them to draw attention.)
I don't like your poll sir. LOL
If you take the "U" out of "STUD", you get STD. I'm just saying.