What are your "must-see" episode suggestions for each series?

Oh this looks like fun! I'll just go with episodes I personally love or think of as classic episodes for whatever reason. I could do like hundreds, but in the interest of time I'll limit it to really special ones. This is hard because there are so many little moments I want to include, but the entire episode wasn't as important. Looking at my list after it wound up being personal favorites more than classics and I know my tastes aren't typically the norm, but whatever!

Original Series:
The School of Hard Knocks
The Ghost of Maiden's Peak (sorry to copy, but I really feel that one is a classic)
Pokemon Fashion Flash
Ditto's Mysterious Mansion
Go West Young Meowth
The Crystal Onix
The Wacky Watcher
The Chikorita Rescue/Chikorita's Big Upset/Current Events/Turning over a new Bayleef (personal love for Chikorita)
The Fortune Hunters
Air Time
A Hot Water Battle
Houndoom's Special Delivery
The Light Fantastic
Fly Me to the Moon
Just Waiting on a Friend

AG:
Seeing is Believing
Now that's Flower Power
A Poke-Block Party
A Double Dilemma
Claydol Big and Tall
Who, What, When, Where, Wynaut?
The Right Place and the Right Mime
Time Warp Heals all Wounds
Once More with Reeling
Celebi and Joy [Chronicles]

DP:
Borrowing on bad Faith
Steamboat Willies
Malice in Wonderland
A Full Course Tag Battle
Ghoul Daze
Noodles Roamin Off
Historical Mystery Tour

BW:
Cilan takes Flight
Battling the Leaf Theives
Piplup, Pansage, and a Meeting of the Times
Team Rocket's Shocking Recruit

XY:
The Cave of Mirrors
Bonnie for the Defense
Under the Pledging Tree
Rotom's Wish
A Frolicking Find in the Flowers

SM:
Mallow and the Forest Teacher
Tasting the Bitter with the Sweet
A Haunted House for Everyone

Not ready to do Journey's yet, plus I know I missed some, maybe I'll edit this post again in the future!