Gerald Rudolph Ford was the 38th President of the United States. for more info on him see his Entry on wikipedia.
Gerald Ford visited Point Place in the episode Streaking, in this episode Red gets chosen as the regular man who can ask Ford one question. Red begins writing down idea's on what to ask, but Jack Burkhart's committee wants Red to ask a question they wrote: "What has been your favorite Parade?". The boys Plan to streak during the meeting while wearing masks (Kelso, Hyde and Fez as Snoopy and Eric as Nixon).
At the meeting Ford trips 3 times while walking to the podium, which he reaches, and then trips again. The boys decide not to streak at the last moment because of all the secret service around.
When it's time for Red to ask his question he doesn't know what to say, so Eric puts his mask on and throws off his trenchcoat and runs through the public naked, giving Red inspiration to ask his own question which is: "How the hell could you pardon Nixon?".
Whe never see the answer but probably Ford didn't know how to answer.