If you made the mistake of watching Fox's "Roseanne: An Unauthorized Biography" last night, you've got two chances to watch the real Roseanne tonight and get the taste of Denny Dillon's hideously bad portrayal out of your mouth. There's also an unofficial reunion on TV tonight, with Bill Cosby and Phylicia Rashad appearing on separate shows, and an official one, with Robert Plant and Jimmy Page, formerly of Led Zeppelin, doing an "Unledded" concert on MTV.
* "The Cosby Mysteries" (8-9 p.m., Channel 2) -- Bill Cosby continues his NBC successes: Last week this show ranked a strong second in its time slot, beaten only (and only slightly) by "Beverly Hills, 90210" on Fox. NBC.
* "Roseanne" (9-9:30 p.m., Channel 13) -- Dillon pretending to be Roseanne proved just how good, in this setting, the real Roseanne is. ABC.
* "Touched By an Angel" (9-10 p.m., Channel 11) -- Rashad, Cosby's on-screen wife on "The Cosby Show," plays an alcoholic journalist, in an episode also featuring Erica Gimpel, once a co-star on "Fame" -- which, as these guest-star roles prove, is fleeting. CBS.
* "The American Experience: FDR" (9-11:30 p.m., Channel 22) -- Part 2 of 2. This second, longer installment of "FDR" is better than the first, but still seems somewhat cursory. It's intriguing, and certainly worth watching, but is neither comprehensive nor surprising. PBS.
* "Turning Point" (10-11 p.m., Channel 13) -- This story isn't new -- it's a return to the 1993 story about tainted hamburgers that sickened or killed certain Jack in the Box patrons. But the grief and anger of the parents is no less raw a year later, and the corporate and governmental finger-pointing and excuse-making documented by correspondent Meredith Vieira and producer Michael Mierendorf is no less depressing. ABC.
* "Jimmy Page/Robert Plant (Unledded)" (10-11:30 p.m., MTV) -- MTV gets the Led out: Songs performed by Jimmy Page and Robert Plant include "Kashmir," "Gallows Pole" and some new collaborations, including "Wonderful One."
* "The Larry Sanders Show" (10:30-11 p.m., HBO) -- Roseanne is here, too, playing herself -- and playing herself very well, in a funny "Sanders" with a surprise season-ending cliffhanger I won't ruin. Watch earlier in the show, though, for a great and well-timed in-joke in which Garry Shandling's Sanders, and Roseanne's Roseanne, poke fun at the absurd insignificance of being dramatized in a Fox movie biography.