The footage at the beginning aired as part of the penultimate episode of 'Freaks and Geeks' (episode 17) in 2000; the raw footage is from one of the two extra DVDs included with the special eight-disc F&G collection. (The collection sold in stores only has six discs.)
In 1990, a year or two before he became super-famous, Rush Limbaugh guest-hosted Pat Sajak's short-lived talk show. It didn't go so well. Details here: www.panopticist.com/ archives/187.html
This 1993 clip is from the debut episode of Chevy Chase's legendarily disastrous late-night talk show. The guest is Goldie Hawn. Prepare yourself for one of the biggest train wrecks in the history of television. More details here: www.panopticist.com/ archives/192.html
A clip from a classic low-budget compilation of horror stories that ran on public access in Bloomington, Indiana, starting in the early '80s. More info here: www.panopticist.com/ archives/253.html