Usher was awarded top honors as best R&B artist and for best album for "Confessions." His single "Yeah!," featuring Ludacris and Lil' Jon, won for best R&B track and "Hook-Up" won for best collaboration.
Lohan won awards for her film work, including best actress in a comedy, best movie hissy fit and best movie blush for her role in "Mean Girls." She also won the film breakout star actress award.
Blink-182, who performed during the show, won for best love song for "I Miss You" and shared tour-of-the-year honors with summer tour partner No Doubt.
Britney Spears' "Toxic" was named best single and Ashlee Simpson's "Pieces of Me" won the song of the summer honor.
Simpson, who also won the "Fresh Face" award, performed during the show, as did Lenny Kravitz and JoJo.