Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Right Click (Or control+click) and there should be a "show view options"

At least in Tiger there is, Leopard may not have it there, but I don't see why they wouldn't, so it's worth a shot


I usually have it set to "keep organized by name" and I don't get overlapping.



Alternatively, there are other view styles, like Grid view which I like the most. But you're staying with that icon view, then view options is your best bet
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.