It's not exactly the computer who's dumb here. You've not played against it's full strength, Shredder is excellent in limiting it's strength so that it can give you a level game. You need to change it to full strength if you want to get beat all the time.
Oh and I just noticed the link you gave isn't shredder. Maybe you're confusing shredder with little chess partner, which is far weaker than shredder.
Shredding Shredder with the Stephenson Attack.
1.e4 e5 2. Bc4 Nf6 3. Nf3 Nxe4 4. Nc3 Nxc3 5. d2xc3 f6 6. Nh6 g6 7. Qd3!?