In today's game? I wouldn't take Bradshaw personally. I'd want some one that could throw it all over the field with accuracy and Terry being a career 51.9% with only 2 more TDs than INTs tells me for the style of offense I'd want to run he'd be a liability.
Joe Montana is a pretty safe bet...high completion %, low INT ratio, proven winner in big game moments...
But I'd actually take Steve Young or Aaron Rodgers if all other thing are equal (OL, skill players, and defense).
Young: 64.3% and just 2.6% for INT % (same as Montana)
Rodgers: 65.3% and just 1.4% for INT % (lowest in NFL history for a career)
Both can also run when needed. Rodgers has over 3400 rushing yards with a 4.8 YPC and 35 TDs. Young had over 4200 rushing yards with a 5.9 YPC and 43 TDs.
So for me at least
1a. Steve Young
1b. Aaron Rodgers
2. Joe Montana