In tournament, a player drew all of his 5 tournament games and scored 2.5 out of 5. Another player got the same score, but he got 2 won, 2 lost, and 1 drew. Which player has a better performance?

I would guess it depends on the caliber of the opponents.

Better to DRAW than LOSE!

Some people hate to lose the game. They prefer to have draw rather than to have win or lose. For me, I like to draw all games. If I have a draw, I feel like I have a win.  When  I lost the game,  I feel  very unhappy.

for me, it is better to draw than lose, too.  however, i don't try to draw all games.  if my opponent is rated higher than me, even if i am slightly (a pawn or i have better position) ahead, and my opp. offers a draw i will take it knowing i might screw up and thus blow the win.  if i am ahead slightly and, say it's a "pawn and bishops of opposite color" endgame.  my opp. offers a draw, i refuse and try to push the pawns (often very poorly lol).  i don't know where i'm going with this, but i'd say the answer to the question is, as ikagan said, "depends on the caliber of the opponents."