ROSIE O'DONNELL returns to daytime television for a one-hour visit with RACHAEL RAY -- and ET/The Insider has your sneak peek!

Rosie spoke candidly about her own talk show experiences, even revealing her worst guest ever!

"I had KEANU REEVES once who totally had no interest in speaking ... and it was live. So I finally said, 'Keanu, I hate to tell you this, but it is a talk show. You have to talk.'"

She also spoke about her time at "The View," saying, "This is an amazing medium if you can use it in the right way. But what I learned from this is that it's much better when I'm the boss."

As for her old boss, BARBARA WALTERS? "I have nothing but respect and reverence for her ... and for who she is. A daytime talk show host, a world-renowned journalist. She has talked to every world leader, before women were not allowed to even dream of doing that. She is a hero. She's a feminist hero whether or not she knows that."

Rosie made quite an impression on Rachael! "Oh my, God. Rosie is such a blast," she told ET's STEVEN COJOCARU. "I love her. There were production numbers; there was a piano; there was confetti; there was crafting; there was food; there was song. It was one of the greatest days ever."

Rosie also gives Rachael a crash course in crafts, as she promotes her new book, Rosie O'Donnell's Crafty U: 100 Easy Projects the Whole Family Can Enjoy All Year Long, now in stores.

"I think it must be our most entertaining hour yet," Rachael enthuses. "She is funny. She sits at the kitchen table. She is very self-effacing, open and lovely. Then there is a lot of crafting and hijinks going on, but I can't give up the big finish."