Go here, fill in the info, download the latest drivers. AMD Graphics Drivers & Software
When you're done, go to the Control Panel and uninstall your current drivers. Express uninstall. Reboot, install the drivers you just downloaded.
You can't do anything about your screen resolution... it is what it is. LCD's and LED's do best when they run in their native resolution. They can do lower resolutions just fine, but it never looks as good as native. So, always pick your graphics card based on your monitor's resolution. You need a card that can do whatever you want it to at 1920x1080. We're never going to push that low end card fast enough to make gameplay sweet at 1920.