You should be able to tab to the choice and hit Enter as most buttons allow in these cases.
This may also be a screen resolution problem resolved by trying another - type Screen Resolution in Start Search box.
However if you have a bunch of toolbars stealing real estate on your browser then I'd immediately uninstall them in Control Panel>Programs and Features as each is spyware that diminishes performance by about 10%.
In fact if you haven't yet I would do what most tech enthusiasts do with a store bought PC and Clean Reinstall - Factory OEM Windows 7
for much better performance without window-obscuring bloat.
At the minimum Clean Up Factory Bloatware