I was not able to send a PM due to being limited to 6 message in 24 hours. So. . .
Thanks for responding. Have you ever tried Fritz 6? Apparently, it is free for chess. However, I do want something that really helps me to learn. If I am not wrong, GreenPawn does not think that Fritz 6 really teaches why things are so, but just shows the continuations that could be. I really want something that can teach me positional or tactical things.