I'm designing a build that should be capable of recording/editing gameplay from games such as TF2, Dayz, etc. I've chosen the Gigabyte GeForce GTX 750 Ti 2gb as my graphics card and I'll be recording with Shadowplay.
Is my graphics card Shadowplay compatible or is it just the NVidia cards?
You're in the wrong mindset here. There is no functional difference between any vendor's graphics cards. They all use GPUs straight from Nvidia, so of course they are compatible. You simply need any GTX660 or later series GPU to use Shadowplay.