Unless I'm not remembering the first two episodes correctly I think the first thing that could be considered a flashback was in the third episode when Peter is recounting what happened at Cheesy Charlies, also in the same episode we flashback to Lois being stuck in the kitchen during Meg's first birthday.
"Feels So Good" by Chuck Mangione
John Bena Ramsey
Either a cutaway or flashback is the type of joke that is commonly used to break up the main story on Family Guy.
A little vague but I think you're referring to "Chick Cancer"
His age has (so far) never been stated but he was a young pilot in his WWII flashback from 'German Guy' so he could be around 20 to 35 years old.
Yuki has a flashback about Zero joining their family in the second episode of Vampire Knight. In that episode, Yuki remembers how Zero was taken in by her father and brought to live with them after losing his family to a vampire attack.
Family Guy aired its first episode January 31, 1999.
Death Has a Shadow
The "chick" that looks like an ant-eater is Renee Zellweger and the song playing in the background is called Roll To Me by Del Amitri.
The first by a long shot
16
All in the Family - 1971 Flashback Mike Meets Archie 2-5 was released on: USA: 16 October 1971