1. Yes Madden 11 Franchise Mode
2. Yes, for the most part it's the big name players. Though they won't become available until the off-season in Year 2. For example, I changed Mark Brunell to "Jim Harbaugh" since Brunell always retires after year 1, and so I kept Mike Singletary around another year and hired "Jim Harbaugh" in my third year in my 49er Franchise.
3. Good question, not sure.
4. Yes you can hire different OC and DC
5. No, you can't be fired, so basically for the whole Franchise your the GM and can't be fired unless you stop playing that Franchise.