I am trying to install Snow Leopard but the mouse stands in the left high corner, When I move it, it returns high there. I cannot clic anywhere, and I cannot install only using keyboard,
Where this problem is coming from ?

Motherboard : MSI H61M-E33
processor : i5 2400 sandy bridge
Graphic card : Geforce 9500 GT
Iboot + Snow Leopard Retail