Sounds like you may have a hardware issue. I'm assuming you are writing about the touchpad rather than a mouse (since "mouse pad" is the title of your post).
I'm unsure of what you mean by "it won't scroll down when i try through the side ". I know the Sentelic 9.1.7.7 driver scrolls by dragging 2 fingers in the direction you wish to scroll.
How long have you had this laptop? If you are still within the period where you may exchange your defective laptop for a new unit or return for a refund, that is what I would recommend.
If you are beyond the point of a return for refund, I would try uninstalling your current touchpad driver and rebooting so Windows 7 installs its Plug N Play touchpad driver. If the issue persists (and I'm thinking it won't correct your right button issue), you'll need to RMA your laptop for touchpad replacement.
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT