Mine are:
The Wedding
Mama Gets a Job
Alien Marriage
Mama's Silver
The Return of Leonard Oates
Supermarket
No Room at The Inn
Where there's smoke
No Fangs Mama
The Best Policy
Bed and Breakdown
Psychic Mama
Zirconia's are a Girl's best friend

This was a hard one, but if I had to choose, these would be considered my favorites from greatest to least:

The Wedding: Part 2
The Wedding: Part 1
Country Club
No Room at the Inn
Rashomama
Ellen’s Boyfriend
Harper Versus Harper
Supermarket
Soup to Nuts
Steal One, Pearl Two
Porn Again
Farewell, Frannie
The Best Policy
Child’s Play
I Do, I Don’t
Have It Mama’s Way
Workman’s Holiday
The Really Loud Family
Mama Cries Uncle

In no real order ...
The Wedding, both parts. No other episode remotely approaches this one for me.
Farewell, Frannie
Best Medicine
Rashomama
An Ill Wind
The Return of Leonard Oates
Cellmates
Positive Thinking
Aunt Gert Rides Again
Mama Gets a Job
No Room at The Inn
Mama Learns to Drive
A Grave Mistake
Cat's Meow
The Really Loud Family
Bye-Bye – Baby!

As you can tell, Seasons 2 and 3 are my favorites.