When I was a young teenager, my crushes were:

Susan Dey as Laurie Partridge

Maureen McCormick as Marcia Brady
But then "grown up women" weren't so bad either...

Barbara Eden as Jeannie

Elizabeth Montgomery as Samantha ("Bewitched")

Barbara Feldon as Agent 99 ("Get Smart")
Many, many years passed, and as a fully grown 40+ year old I got a crush... again...

Young Courtney Cox in Friends

Alyssa Milano at the beginning of her career in "Charmed"
These days... I'm too old to get a crush... I think...
I do have a soft spot for Nordic lore, though...

Angelina Jolie in "Beowulf"