What lighting setup is recommended for filming a presenter in front of a TV screen?
If you can't use green-screen (the ideal), I'd recommend a couple of things. First, use a screen with a matte surface to reduce specular reflections and present more diffuse ones. These are somewhat rarer that glossy ones. 

Second, angle the screen slightly top-forward, to deflect some reflections down and away from the camera. A slight parallax won't be too noticeable. Same goes for a slight off-axis view right-to-left

Third, try a polarizer in front of the taking lens to dampen some reflections.

Last, use cutting flags on all fixtures to minimize the amount of light that actually touches the screen. If you keylight from two directions, you can help avoid hitting the screen. Diffuse fill light is much harder to flag effectively.

Good luck. I'm sure others here will have more suggestions.