Since your drive wasn't partitioned, it'll take a little longer to fix. But now is a good time to redeem yourself. It'll make things a lot easier for other times as well.
What you can do is, repair your current installation by booting with the Windows cd and choosing the right options when aksed to.
Once that is done and inside Windows (it should be working), format your new drive through the disk manager and copy your important files on it.
Then, do a clean install of Windows on your c: drive, after having formatted and partitioned it. C: has to be for the OS only and should be at least 5gb (with the pagefile on another partition) as files pile up on c: even if you never install anything on it. Divide the rest in themes like apps, games, etc.