I have a HP G62 laptop and my vertical scroller isn't working?

-On the HP helping website it told me to

go to Control Panel -> Mouse -> click on last tab (Device Settings) -> click on + next to the second item(Scrolling) ->click on "one finger scrolling"(don't click on the + next to it, just click on it's name) -> check whether "Enable vertical scrolling" is checked or not... if not check it....



but it wont let me check it. And when ever I open up the 'Mouse' option in the control panel this thing pops up saying to uninstall Synaptics and the install it again or something.... I just want my scroller to work. HELP!