a randomiser routine goes something like this
Code:
rnd = 10;
choices = []; // where to store the chosen questions ref.
questions = ["","",""]; // the questions 
while( rnd-- > 0 ){
  do{
  rand = ~~(Math.random() * questions.length) | 0;
  }while( choices.indexOf( rand )>-1 ); // have we already chosen this
  choices.push( rand );
}
one way of storing the questions could be :
Code:
questions = {
    0:{question:1, text:"What is this about?", answers:["Eating cheese","Picking your nose"], score:[0,1]},
    1:{question:2, text:"When is this?", answers:["Last week","Next year","Friday Week"], score:[0,1,2]},
...
}
so the question is questions[ n ].text, what the score is for the correct answer is in questions[ n ].score which is an array and I think you can guess the rest.