Question

Preferably with just javascript. But if that’s too hard, jquery will be ok (I don’t want to load jquery because the page has to load really fast).

Answer 1

This question is pretty ambiguous, and I get the impression that you might be a little confused in your wording. This handler will disable the horizontal scrollbar if the body width exceeds 1000px, and the vertical scrollbar if the body height exceeds 600px. If this is really the functionality you’re looking for, you should be aware that it’s likely to frustrate users who are used to having full control over the scroll position of the page. Anyway, here’s what (I think) you asked for:

function scrollStuff()
{
    if (document.body.offsetHeight > 600)
    {
        document.body.style.overflowY = 'hidden';
    }
    else
    {
        document.body.style.overflowY = 'auto';
    }
    if (document.body.offsetWidth > 1000)
    {
        document.body.style.overflowX = 'hidden';
    }
    else
    {
        document.body.style.overflowX = 'auto';
    }
}

window.onload = scrollStuff;