Touch pad/Cursor Working Improperly

I wasn't sure in which section to post this -- the touch pad is indeed hardware, but I'm certain this isn't a hardware problem.

Anyway, I just cleaned up my computer. Deleted junk files (nothing crucial to normal operations, I'm sure), and shut off some automatic start-up processes. Then I restarted my computer, and after doing so, my touch pad no longer allows me to scroll by sliding my finger along its edge. This has happened before and usually fixes itself.

But I am also now unable to double-tap the touch pad and drag windows, or drag anything else for that matter. When I try, the area will be responsive for a moment (ex: the page's scrolling bar will darken), but then returns to the state it was in before I clicked it -- basically behaving like a single-click. It's frustrating.

Both left and right buttons work, and single-tapping still works, in that I can tap inside this text box to move around. But I can't double-tap to highlight text.

I'm using a Lenovo Win7 PC model, Windows 7 Home Premium, and 64bit, if that makes any difference. And yes, I have tried typing "mouse" in the search box and toying with the settings.

Fixed it. In case anyone is having the same issue, try:

Click Start > type "mouse" > click Mouse when it appears > Hardware tab > click Roll Back Driver and allow it to roll back > click Update Driver > restart your computer.

This basically refreshes the settings that may have been disturbed beforehand. I don't know why I didn't think of it sooner.