William Theodore Walton III averaged 20.3 ppg, 15.7 rpg, and shot 65% from the field, so picking out a "best" game in a sterling career like that is making a stretch. (Those of you dreamers who think Michael Jordan was the best college player can forget it.) However, it would be hard to see anyone playing a better game than the one Walton played against Memphis State in the 1973 NCAA Finals.
In only 33 minutes ("only" because how could he get those numbers in 33 minutes?), he hit 21 out of 22 shots from the field, pulled down 13 rebounds, and had 2 assists and a block for good measure. And with 6-9 Larry Kenon getting 20 points and 8 rebounds for Memphis, it is not as though there was no talent on the opposing team. I actually watched that game live, and I was not a UCLA fan back then, so I did not appreciate what I was watching until years later when I looked at the statistics. I got to see live one of the most amazing performances in college basketball history.
And, for the record, no, even Bill Walton was not the best college player of all time. That award clearly goes to Kareem.