very easy question to answer.
Reina in goal, best keeper in the world as far as I'm concerned.
Carra at right back because Finnan is knocking on and it gives us a chance to blood Agger and Skrtel together early.
Agger and Skrtel at the back obviously by my line above. Both quality, young central defenders. They're more than likely going to be our pairing in the future, sort it out now.
Arbeloa at left back. It's where he's played all his best games in a Liverpool shirt, especially at the Nou Camp where he marked Messi out of the game. Our other options for left back just aren't up to the task, unless we give Insua a real go in the side who is another massively talented youngster.
Right wing has to be Gerrard. The rest down the right are useless and can't cross wires never mind a football.
Mascherano and Alonso in the middle becuase they are simply two world class midfielders. If Alonso gets this more advanced role then we'll be laughing because Mascherano will mop up everything and we'll see Alonso's ability going forward much better.
Left wing is Babel. A very good player who will only get better. Again our replacements might as well not exist.
Up top is Keane and Torres. No explaination needed really.