No, Keeler is dead. However, Fox would not allow them to kill a sitting President on screen. However, all of the producers & writers have said in interviews that Keeler is dead.
4. What ever happened to Beerooz?
He was rescued by Curtis and taken back to CTU. There is a deleted scene of this on Disc 7 of the Season 4 DVD's.
5. Did Tony Almeida die in season 5 and if so how?
Yes, Tony died in episode 5.13. He was preparing to inject Christopher Henderson with a lethal dose of drugs as payback for the death of Tony's wife, Michelle Dessler. However, Henderson wasn't unconscious as everyone thought and he grabbed the syringe and stabbed Tony in the heart. Jack arrived just in time to hear Tony tell him "She's gone, Jack." (referring to Michelle) and then he died in Jack's arms.