Annette is correct. Or you can go into your profile and Unsubscribe to individual threads there while keeping e-mail for the ones you want.
Daniel was 4 1/2 in 1969
Teal'c was 104 a month after THE LIGHT (Season 4) and will be 104 in Season 5.
Jack is in his early or middle 40's about 8 to 10 years difference from RDA's age. He greyed early.
Sam is in her early 30's.
Janet is the same age or middle thirties.
Hammond is around 60... DSD keeps his hair short for the role as it is still red (saw him in Hostage Negotiator filmed late last year and it was red and longer for that role).