Halo Carded Pez are those that are on the discontinued Pastel Striped cards and have a white "Splash" behind the characters head. The more common had only the Pastel Stripes and were produced after the Halos.
Here is the list of PEZ Dispensers reported on halo cards to date:
Angel
Arlene
Bambi
Barney Bear
Barney Rubble
Bouncer Beagle
Bugs Bunny A
Bugs Bunny
Charlie Brown w/smile
Charlie Brown w/frown
Chick, hard green shell
Chick, hard red shell
Chick, soft red shell
Chip, pink face
Cool Cat
Daffy Duck
Daffy, split beak
Dalmatian Pup
Dewey (blue cap) duck nephew
Dino
Donald Duck B
Donald Duck, mouth closed
Dr. Skull
Droopy A, movable ears
Droopy B
Dumbo
Easter Bunny
Fat-Eared Bunny
Foghorn Leghorn
Fozzie
Fred Flintstone
Garfield smiling (older version)
Garfield w/teeth
Garfield w/visor
Gonzo
Goofy
Goofy C
Gyro Gearloose
Huey (red cap) duck nephew
Jerry (brown mouse), multi-piece
Kermit
King Louie
Lamb
Lil Bad Wolf
Louie (green cap) duck nephew
Lucy
Merlin Mouse
Mickey Mouse A
Mickey Mouse C
Miss Piggy
MMM Camel
MMM Clown
MMM Donkey
MMM Duck
MMM Frog
MMM Indian
MMM Koala
MMM Lamb
MMM Lion
MMM Monkey
MMM Panda
MMM Parrot
MMM Penguin
MMM Pig
MMM Rhino
MMM Rooster
MMM Tiger
Mowgli
Nermal
Pebbles
Petunia Pig
Pluto
Pluto, movable ears
Practical Pig, wavy hat
Pumpkin
Road Runner, painted eyes
Road Runner, stenciled eyes
Rudolph
Santa
Santa, blind
Scrooge McDuck A
Scrooge McDuck B
Snoopy
Snowman
Speedy Gonzales A (no bandana)
Spike B
Sylvester
Sylvester, cream face w/whiskers
Tom, multi-piece face
Tuffy (grey mouse)
Tweety
Tyke
Webby
Wile E. Coyote
Witch
Witch, 3-piece
Wonder Woman, raised star
Woodstock, no feathers
Woodstock w/feathers
Maybe we should have listed what was *not* on halo?!