Don't know about the second; haven't seen that part yet.
The actress' name is Michelle Forbes. According to IMDB, she was on Season 2 of "24". I didn't remember what happened to her character, but according to the "24" Episode Guide the last she was seen, she was being put into an ambulance after her fall.
If I may geek out a little bit... I'll always remember that actress for two roles she played: Ensign Ro on Star Trek: TNG and good twin/evil twin Sonni/Solita on "Guiding Light", way back in 1987-89 (her first role, apparently!)
We think she also played the coroner on Homicide:Life on the Street.