It looks like this should do the trick:
jQuery('input[type="checkbox"]').remove();
However, buyers who are unable to figure out how to remove an item will probably just abandon their order entirely rather than placing their order anyway with an item they don't want. If you could explain why you want to do this, perhaps we could suggest another approach less likely to affect your conversion rate. For instance, we know of sellers who use custom javascript to auto-remove an item from a buyer's cart when another item it's dependent on is removed.