error installing Ubuntu Studio

[Draexo]

I had previously installed Ubuntu and Ubuntu Studio in dual-boot with Windows 7 configurations, but I still consider myself a newbie at it.

I purchased a new hard drive a few months back and started everything from scratch. Today I just got around to installing Ubuntu Studio and I received this message

"Executing grub_install/dev/sda failed. This is a fatal error"

Now what?

[Draexo]

When I try to install again, it tells me Ubuntu Studio is already installed.

[Draexo]

Well, I got it working, however, I would like Windows to be the default boot option and instead it is Ubuntu. How do I change that?