Pretty straightforward, but nice.
Bogoljubov vs Alekhine, 1922
(A90) Dutch, 53 moves, 0-1
Nice queen sacrifice, although forced!
Alekhine vs A Fletcher, 1928
(A31) English, Symmetrical, Benoni Formation, 32 moves, 1-0
Well too complicated for me, but everyone says great.
Reti vs Alekhine, 1925
(A00) Uncommon Opening, 40 moves, 0-1
Too nice a mate!
Letelier vs Fischer, 1960
(E70) King's Indian, 23 moves, 0-1
I am sure a lot are not forced, but that is the beauty.
D Byrne vs Fischer, 1956
(D92) Grunfeld, 5.Bf4, 41 moves, 0-1
Deep Blue vs Kasparov, 1997
(B17) Caro-Kann, Steinitz Variation, 19 moves, 1-0