Laptop resolution running XP

I’m using a HP Pavillion zv6000 running windows xp. I have a 15.4 widescreen display. The icons are larger than they need to be and I would like more space so I tried boosting the resolution. Unfortunately, whenever I go higher than ~1200 x 800 (default) I get a scrollable desktop. For example, my icons don’t get smaller and spaced closer together…they stay the same but I can move the mouse across the screen and scroll to free space. Is there any way around this??