Oh man, too tough to choose but I'll try anyway, skipping the two Greatest Hits compilations:
White Album: Rhiannon, I'm So Afraid, Landslide
Rumours: All of LB's songs, The Chain, Silver Springs (this counts because I have the DVD-A
)
Tusk: Tusk, Save Me a Place, I Know I'm Not Wrong, Beautiful Child
Live: I'm So Afraid, Fireflies
Mirage: Oh Diane, Straight Back, Hold Me
Tango: Big Love, Little Lies, Tango
Behind the Mask: Never heard the album, but I have heard songs from it, so if I have to choose, I'd say Paper Doll
Time: Never heard anything from it
The Dance: Big Love, Bleed to Love Her, I'm So Afraid
Say You Will: Red Rover, Peacekeeper, Thrown Down, Come