The stock heatsink has terrible performance to noise ratio, but is sufficient for most of your every day tasks and a mild OC. I currently have my old 1055T running a 3.6 ghz oc being used as a family computer for light gaming and general web browsing. The noise is the one thing that annoys me more than anything else, as I can hear it from the next room when it is working hard. The other thing to consider is what you actually do with your computer. If you're constantly rendering videos in Sony Vegas, the stress on your processor is going to be much greater than gaming, and you might want to look into a beefier cooler.
If you are intimidated by the top air coolers like the D14, Silver Arrow, Megahalems, you don't have to get those. If you live in a cooler area, you could get by with something cheap and light like a CM 212+/EVO for around $30-$35 USD. The Scythe Mugen 2 is also one of the better budget coolers, but it is a PITA to mount.
There really is nothing to worry about. Your motherboard isn't that fragile and won't break from having a big heatsink mounted. If that were the case, many of us here wouldn't be able to post on this forum with a working computer