Blair - Emma Roberts
Tootie - Keke Palmer
Natalie - Kallie Flynn Childress
Jo - Joanna 'JoJo' Levesque
Mrs. Garrett - Jane Fonda

Mrs. Garrett ~ Doris Roberts

Blair ~ Jessica Simpson

Jo ~ Jessica Alba

Natalie ~ America Ferrera

Tootie ~ Rihanna

Mrs G: Joy Behar
Natalie: Nikki Blonski
Blair: Amanda Seyfried
Jo: Missy Peregrym
Tootie: Taylor Parks

Blair - Blake Lively
Tootie - Shareeka Epps
Natalie - Nikki Blonsky
Jo - Michelle Trachtenberg
Mrs. Garrett - Kelly Bishop

Blair - Amanda Seyfried
Tootie - Raven-Symoné
Natalie - Nikki Blonsky
Jo - Amanda Bynes
Mrs. Garrett - Caroline Rhea

Blair - Hayden Panettiere
Tootie - Monique Coleman
Natalie - Nikki Blonksy
Jo - Zooey Deschanel
Mrs. Garrett - Brenda Blethyn

oh my god, natalie was a hard one to pick a character for...

Blair - Hayden Panettierre

Tootie - Meagan Good [when she had braces in the famous jett jackson, she def. reminded me of tootie]

Natalie - Kaycee Stroh [High School Musical] OR Nikki Blonsky [Hairspray]

Jo - Jessica Biel [they have similar smiles and eyes]

Mrs. Garrett - Katey Sagal (w/ red hair) [they have the EXACT face pretty much]

Blair-Nathalia Ramos[frm:bratz-the movie(2007)]
Tootie-Kyla Prat
Natalie-Nikki Blonsky
Jo-Lacey Chabert
Mrs. Garrett-Ana Gasteyer

Blair~Lindsay Lohan
Tootie~Keshia Knight-Pulliam
Natalie~Nikki Blonsky
Jo~Amanda Bynes
Mrs. G~Mindy Cohn

Blair - Sara Paxton
Tootie - Keke Palmer
Natalie - Kaycee Stroh
Jo - Amber Tamblyn
Mrs.Garret - Debbie Reynolds

Blair- Amanda Seyfried
Tootie- Raven Simone
Natalie-Nikki Blonsky (Traci in 'Hairspray')
Jo- Eliza Dushku
Mrs. Garret- Reba McEntire

Blair- Heidi Montag (The Hills)
Tootie- Lil Mama (Rapper)
Natalie- America Ferrera (Actress)
Jo- Michelle Rodriguez (Actress)
Mrs. Garret- Sharon Gless (Actress- "queer as folk")

Blair - Jessica Simpson
Tootie - Jennifer Hudson
Natalie - Tina Majorino
Jo - Jordana Spiro
Mrs. Garrett - Bette Midler

Blair -- Amanda Bynes
Tootie -- Jennifer Hudson
Natalie -- Emma Roberts
Jo -- Jenna Malone
Mrs. Garrett -- Queen Latifah

Blair (Alice Eve - "Starter for Ten")
Tootie (Tessa Thompson - "Veronica Mars")
Natalie (Kat Dennings - "40 Year-Old Virgin")
Jo (Martha MacIsaac - "Superbad")
Mrs. Garrett (Melora Hardin - "The Office")

I think schnappycat nailed it!

Blair: Hayden Panatierre
Tootie: Keke Palmer
Natalie: Rachel Weisz
Jo: Patricia Arquette
Mrs. Garrett: Bette Midler

Blair - Hilary Duff
Tootie - Raven-Symoné
Natalie - Mandy Moore
Jo - Liv Tyler
Mrs. Garrett - Annette Bening

Blair - Liza Weil (yes she's a bit old for the part now, but she basically was a new version of Blair on Gilmore Girls)

Jo - Scarlett Powers (from Reba)

Tootie - Raven

Natalie - America Ferrara

Mrs. G - Kathy Najimy

Blair: Missi Pyle
Tootie: Raven
Natalie: Jenna Von Oy
Jo: Laura Prepon
Mrs. Garrett: Debra Jo Rupp

I don't think typecasting is really necessary, so here are my picks. The castings from 'That '70s Show' would bring in viewers!

Based on these ladies comedic timing:

Queen Latifah as Mrs. Garrett
Kristen Bell as Jo
Amanda Bynes as Blaire
America Ferrara as Natalie
Raven as Tootie

oK upfront, my cast is probably not in the spirit of what the challenge had in mind, but it was fun thinking up.

Mrs. Garrett - Shirley MacLaine

Blair - Angelina Jolie

Tootie - Countess Vaughn

Natalie - Camryn Manheim

Jo - Marisa Tomei

And as a bonus:
Beverly Ann Stickle (Cloris Leachman's character) - Jane Fonda
Her Son Andy Stickle - Sean Hayes
George Burnett (played by George Clooney) - Ashton Kutcher

Blair (Brittany Snow)
Tootie (Keisha Knight Pulliam)
Natalie (Nikki Blonsky)
Jo (Lizzy Kaplan)
Mrs. Garrett (Kathy Bates)

jpullman813- kathy najimy would be a GREAT choice for this recast! good job!

Blair - Jessica Simpson
Tootie - Raven Simone
Natalie - Nikki Blonsky
Jo - Amanda Bynes
Mrs. Garrett - Reba McEntire

PRgirl03, reba's a good pick, forgot she had a sitcom!

Raven-Symoné

Blair - Brittany Snow (American Dreams, Hairspray, Nip/Tuck http://www.imdb.com/name/nm0811242/)

Tootie - Shavon Kirksey (Private Practice http://www.imdb.com/name/nm2058323/)

Natalie - Alia Shawkat (Arrested Development http://www.imdb.com/name/nm0790057/)

Jo - Emma Stone (from Superbad http://www.imdb.com/name/nm1297015/)

Mrs. Garrett - Catherine Hicks (7th Heaven http://www.imdb.com/name/nm0382819/)

Mrs. G - Susan Surandon
Blair - Blake Lively (Traveling Pants)
Tootie - Raven Simone
Jo - Amanda Bynes
Natalie - Nikki Blonksy (Hairspray)

Mrs. Garrett - Bette Middler
Blair - Jessica Simpson
Jo - Katie Holmes
Tootie - Rihanna
Natalie - America Ferrara

Blair---Tyra Banks
Tootie---Lil' Kim
Natalie---Niecy Nash
Jo---Queen Latifah
Mrs. Garrett---Oprah

Blair- Ashley Tisdale
Tootie- lil mama
Natalie- Jordin Sparks (lord knows she needs the work)
Jo- Amanda Bynes
Mrs. Garrett- Diane Keaton

Tootie - Raven Simone
Natalie - Mandy Moore
Blair - Rachel McAdams
Jo - Pink
Mrs. Garret - Lauren Graham

Mrs. Garrett - Kirstie Alley

Natalie - Countess Danielle Vaughn

Tootie - Dakota Fanning

Jo - America Ferrera

Blair - Amanda Bynes

This is my interpretation.

Blair - Mandy More
Tootie - Shar Jackson
Natalie - America Ferrera
Jo - Jesssica Biel
Mrs. Garrett - Fran Drescher

Man! I meant Mandy Moore!

Blair - Elisha Cuthbert
Jo - Michelle Rodriguez
Tootie - Taylor Parks ("Little Inez" from Hairspray)
Natalie - Nikki Blonsky
Mrs. Garrett - Paula Deen

For the win:

Blair: Jessica Simpson
Tootie: Monique Coleman (High School Musical)
Natalie: Brittany Murphy
Jo: Katie Holmes
Mrs. Garrett: Shirley MacLaine (Rumor Has it and Steel Magnolias)

(Loved Michelle Williams for Jo, Jacolina!)

Blair - Scarlett Johansson
Tootie - April L. Hernandez
Natalie - Drew Barrymore
Jo - Pink
Mrs. Garrett - Kathy Bates

Blair- Sara Paxton
Tootie- Kyla Pratt
Natalie- Niki Blonsky
Jo- Michelle Trachtenberg
Mrs.G- Jane Fonda

Blair- Ashley Tisdale (good at acting dumb)

Tootie- Keke Palmer (amazing actress that won many awards)

Natalie- Amanda Bynes (even though not overweight like Natalie I think she can pull off the part)

Jo- Lindsay Lohan (rebellious like Jo)

Mrs.G- Reba

I choose actresses that are around the age they were when the show first started and i think can pull off the characters.

Blair - Brittany Snow

Tootie - Lil' Mama ("My lip gloss is cool, my lip gloss be poppin'...I'm standin' at my locker, and all the boys keep stoppin'!" Does she act? She does now. Everyone loves a crossover celebrity.)

Natalie - Sara Rue

Jo - Michelle Rodriguez

Mrs. Garrett - Tovah Feldshuh

OMG! Other people thought of Lil' Mama and Michelle Rodriguez?! *Hyperventilating* Damnit, I was going for uniqueness!