I believe it was the show in 50s "I love Lucy". She was white and he was Cuban.
young and the restless
The first interracial kiss on American television occurred on November 22, 1968, between Captain Kirk (William Shatner) and Lieutenant Uhura (Nichelle Nichols) on the TV series "Star Trek."
Happy days
I am assuming you are talking about American Caucasians and African Americans. There is no answer to this question. As far back as the good old plantation days there was serious romantic affairs going on, but well hidden.
the Munsters.
Fred and Velma (or Welma) Flintstone.
No. They may have been the first "multiracial" couple on television, if you accept that "of Spanish descent" is a different "race" than "white".
Pat Sajak and Vanna White have been the only hosts for the current Nighttime Show. They were also on the daytime show where Chuck Woolery was the first host to have have the TV series
St Elsewhere
Mary Kay and Johnny were the first couple to appear in bed together in a prime time television show, it was actually the fist sitcom on television in 1947. http://www.snopes.com/radiotv/tv/marykay.asp
Eureka is partially good but lacks the depth after the first couple episodes. Even so it can humor you for a couple of seasons but nothing great about it.
Mike and Carol Brady