string=0;
images=new Array();
images[0]=”5.jpg”;
images[1]=”bild.jpg”;
images[2]=”a.jpg”;

preload=new Array(3)

for(i=0;i<images.lenght;i++){
preload[i]=new Image(120,120)
preload[i].src=images[i]
}
function Number() {
pet=document.getElementById("id");
pet.innerHTML="image" + eval(string+1) +"of" + images.lenght;
}
function Next() {
if(string<images-1) {
string=string+1
document.pas.src=preload[string].src
}
else{
alert("something gone wrong")
}
Number();
}

If this is going to be your main computer, I’d go with the 13″. It definitely has a better battery life than the 11″. I don’t mind the battery life for my 11″ MBA since it hasn’t been an issue so far.

Hope this helps!