Not necessarily “best” in all cases, but some that stick with me (most mentioned already, but some not):
Babylon 5 (2nd season)
Hawaii 5-O (Orig. version)
Rawhide
Mission Impossible (1969)
The Wild Wild West
Star Trek TOS
Secret Agent Man
The Prisoner
The Flintstones (yikes!)
The Twilight Zone
The Addams Family
Green Acres
Gunsmoke (original)
Merrie Melodies Theme (Ingrained in me as a child!!!)
Tonight Show (Carson)
Cosmos Theme (Ya’, I know, but the music was wonderful)
Gilligan’s Island
The Man From U.N.C.L.E.
Mighty Mouse (Ok, what can I say?) :-)
Bonanza
Monday Night Football (original)
Get Smart!
The Wild Wild West
https://www.youtube.com/watch?v=BdbRn9cl0dk
Secret Agent Man
https://www.youtube.com/watch?v=bG0u3-Gbu88
Mighty Mouse d:o)
https://www.youtube.com/watch?v=fJvM8eYcpL0