This is a tough one. The Bears have so many absolute WMDs to choose from among the front seven. However, the secondary would be a slight weakness, only in comparison.
Gotta put Peanut up there, considering all the total takeaways, but who on the other side? Frazier? McAfee? Woolford? Grange? Kind of thin there... Frazier was certainly on his way to a several time PB/AP selection before he blew out his knee in the SB on some trickery. But we basically got two damn years out of him... McAfee got the nod on this video I watched on YouTube recently (A Tradition of Defense) but I never saw him play, so I don't know which way to go. Obviously same with Grange, who cannot be denied. Woolford was sort of a flash-in-the-pan ala Vasher, further mucking up the decision.
Then the safeties. We got some real good ones, actually a few greats. Richie Petibon, Rosie Taylor, Doug Plank, Fencik, Carrier, Mike Brown, more I can't think of right now. For this discussion - ignore FS and SS - just pick the two that you feel would give us the best secondary. Fencik played FS but would've been fine at SS, especially if we had Brown, for example.
Base it off of the athletes they were and what they brought to the table. If they didn't have the career numbers, so what. And for the old-timers, regale us with stories of the guys in the past that we might not have seen for ourselves.
Petibon (didn't see him first hand but he sounds like a bad MF and in clips I like a lot of what I see.)