windows 7 and dual monitors

I just upgraded to Windows 7 64 bit from Vista 64 bit. Everything seems to be fine except for the mouse working from monitor to monitor. I managed to set the display that I wanted as #1 to #1, but I can't get the mouse to act the way that I want it to. The monitors are side by side. The mouse use to cross from one to the other in the center between to two monitors. Now you have to trek from the outside edge of one to the opposite outside edge of the other. I hope that made sense. I have a NVIDIA GeForce GTX 285 video card that says it is working properly.

Can anyone offer up some advice!? Please...