First you go past the dining room table, and take a left. go up the stairs and go into the door straight across from you. Go to the dresser and open the 1st drawer. You will find a letter. Go to the fireplace and get the key. Bring the letter back to the dining room and put it in the bowl. It will read: IV - II. Go back to the dresser and open the 4th drawer, then the 2nd. you will get a wrench. Leave the room, go down the stairs, and take a left. You will se a keg. Go to it and use the wrench. The spikes will fall away, leaving a passage untrapped. Go down the coridoor, and the door will have a note on it saying 78. Go back to the dining room, and go across to the locked room. Use the key, then go in. Once inside, take a left. go into that room, and look at the safe. Set the number on the left to 7, the number on the right, 1 (it will advance to 8 afterward). Once you get the ring, go back to the trapped corridoor. Use the ring on the door, and go down the stairs. Once down the stairs, look at the picture on the wall, then put that combination into the turning thing. Go in the double doors, then go straight across the, room through the single door and get the golden key hidden among the corpses. Go back across the art room and into the bedroom, and use the key on the desk. Get the book, then use it on the bookcase in the art room. Once in the elevator, turn the wheel and turn around, until you see stairs leading down to a room with suits of armor lining the walls. Go down there, and fight the knight. Once you get the sword, go back to the elevator and turn the wheel until you get stairs leading up. Put the sword into the door, and go up there. Turn the lever to the zodiac sign of Saggitarius (it's in a dictionary), and look in the telescope. The stars are green. Then look up Aquarius, and they're light blue. Now push those buttons on the statues outside of the observatory, and the fountain will empty, filling another pool. Go back to the elevator and go to a room with stairs leading down to the pool you just saw. Get the gun from the chest, then head to a big stained glass window, then shoot it. Once in the attic, head down the hall once, then look right. push the wall. Line the dot with the hole (it's easy enough), and go up the stairs. Look at your mom's portrait, and listen to your dad. For the good ending, shoot him. for the bad ending, go to him.
P.S. To get the best ending, you must find all four "psychic cockroaches" hidden in the mansion.