Capture 3 stones has an additional rule: A player may not play a stone so that it creates a past board position. So repetition of full-board position is not allowed.
After the game ends, a result is calculated. Any stones that opponent could capture are calculated as captured. Players points are the sum of following: * The territory he has surrounded, * Captured and capturable opponents' stones. White usually gets some extra compensation for blacks' right to start the game. This is called komi. Hactar uses Japanese rules for calculating result.
Go is usually played in a 19 by 19 board, but smaller boards are better for learning the game. 9 by 9 is the best board to start with. Diagram shows 9x9 board with first three stones played.