A Los Angeles native, Bristow is the third child of former performers Frank Bristow and Patricia O'Kane. He resides in L.A. with Andrew Nicastro, his partner since 1994 and the former Director of Global Production for Steven Spielberg's Shoah Foundation. He and Nicastro were married in April 2010 in a ceremony in Old Greenwich, Connecticut, attended by friends and family.

Bristow has been nominated for a Los Angeles Drama Critics Circle Award, a Los Angeles Stage Alliance Ovation Award, and took home a Back Stage West Garland Award for originating the role of Bob in The Breakup Notebook: The Lesbian Musical, which received the prestigious 2006 Ovation Award for World Premiere Musical. His live show, "Stuffed and Unstrung," was also nominated for a Drama Desk award in 2010 in the category of "Unique Theatrical Experience." Bristow is also an alumnus of the Los Angeles landmark Sketch comedy/improv troupe The Groundlings, where he still occasionally performs improvisation comedy. His film work includes Austin Powers: International Man of Mystery as a tour guide at Virtucon, the cult camp-classic Showgirls, So I Married an Axe Murderer, The Longest Yard, The Twilight of the Golds, Jimmy and Judy, Enigma with a Stigma, and Pain & Gain.

In 2010, he appeared off-Broadway at the Union Square Theatre as Director and stage host of the revamped "Puppet Up", renamed "Stuffed and Unstrung" (co-created with Brian Henson) for its New York debut. The show, a mix of improvised, uncensored comedy sketches and recreations of vintage Jim Henson comedy pieces, garnered rave reviews, including an "A-" from Entertainment Weekly. Bristow is also credited as Director and co-creator (alongside Brian Henson). He continues to teach improv in Los Angeles through his own school/repertory company.