[PowerPC603]

You only need the player with the highest deaths?
Or the highest 10?

You could have a file that holds that information and an array to hold them on the server.

When someone dies, add 1 to their deaths.
Then compare it against the values in that new array and if they have a higher death value compared to another player, put his name in that array and remove the player with the lowest death value.
Then re-save the file which holds these 10 players.

Example:
A 10
B 15
C 7
D 2
E 100
F 16
G 24
H 37
I 45
J 9

These could be the top players on your server and this data should be in that file.
Then your player dies and reaches a death value of 3.
Then you should remove player D and put your player in it's place.
Then re-save the file with the new playerlist.

You may also sort the list in a descending order before saving.

It can be done, but if you want to record all your players (over 1000), it's not that efficient.
Better use MySQL for longer lists.