Selecting View->TopTen from the menu brings up the TopTen dialog box. This dialog box can be used to consult a number of different highscores.
For that, choose a language, a game type, and a grid size in the left frames "Language", "Game type" and "Grid size".
The highscores are then displayed in the right frame, according to the selected options.
Click the "Reset scores" button: the scores are reset to 0, and the players names are reset to "Unnamed".
Click the "OK" button to close the dialog box.