Britney Spears Steps Out For a Good Cause

With her divorce settlement behind her, Britney Spears took time out on Saturday night to do something for the kids, adding star wattage to Jenny McCarthy and Jim Carrey's fundraiser for Generation Rescue, an organization dedicated to researching autism.

"She looked great and seemed really happy," says a partygoer of the Snow Queen Vodka-sponsored shindig at the couple's home in Brentwood. Though she kept close to her assistant Brett and didn't speak to other guests, "She smiled and clapped during the video about autism. She was very into the information and watched a little bit of the dancers from Dancing with the Stars, sneaking out during one of the performances."

Also at the bash were newlyweds Charlie Sheen and Brooke Mueller ("The honeymoon isn't over!" remarked one guest), a "lovey-dovey" Robert Rodriguez and Rose McGowan, who kissed and danced all night, and of course the host couple.

"Jenny and Jim were adorable," says the guest, "She kept saying, 'I love you honey' to him when she thanked him from the stage." Carrey, not to be outdone by the DWTS folks, soon took to the dance floor, even challenging another guest to a playful dance-off.