Here's one suggestion to try: Check to see whether your "desktop" is set to the recommended resolution. Right click the desktop, select screen resolution and under resolution check to see if it says "recommended" after the numbers. If it doesn't, change it to the recommended resolution. If it does say recommended, then it's probably something else that's causing the issue.
That snap feature was one thing I couldn't get used to in W7 so I disabled it. I probably should force myself to try it for a while to see if maybe I can get used to it. But I prefer to have my windows set up very specifically.