I just installed Movie Studio 13. Every time I started it, it would hang in the splash screen when the status being shown was "Initializing GPU-accelerated video..."
This bug apparently goes way back, but all of the suggestions I found either applied to AMD or Intel video processors. I have an NVidia GTX 570. This might work on other NVidia cards as well.
In the NVidia control panel, there is a tab called "Manage 3D settings." That screen in turn has a tab called "Program Settings" where you can customize the settings for each program.
Push the ADD button and point to the Movie Studio application (for 13 it's moviestudioplatinum130.exe). Scroll down the list of settings and turn "Threaded Optimization" to OFF.
For me, this worked. Movie Studio now starts without incident.