Any screen that boasts 100Hz processing is only attempting to improve the signal coming into it. Broadcast TV in the UK uses the 50Hz refresh rate: 100Hz processing is simply applied 'after the fact' to the incoming signal.
24/25fps is entirely unrelated. An example: if you were to buy an open-coded DVD player and replay an American (NTSC) DVD on your TV, it wouldn't be rendered as a 100Hz image: it would be shown at whichever refresh rate is most appropriate for the content. In this instance, that would mean 60Hz (twice the 30 frames per second video of the disc).
Same applies to a TV capable of handling 24fps. It won't, for one moment, attempt to convert that frame rate into a 100Hz signal: 24 doesn't naturally convert to 100, no matter how creative you get with maths. So, it'll handle 24fps at a natural multiple of 24 -ÿmost likely 72Hz, although 48Hz and 96Hz aren't unknown.
One last thing, and don't take this the wrong way: you sound to me like you're buying on specifications. Please, please don't. It might be 1080p, it might support 24fps, it might have HDMI 1.3 inputs and it might have 100Hz refresh -ÿbut that doesn't automatically mean it's a good TV. Some Pioneers we could name, for example, would fail on a few of those criteria -ÿbut that certainly doesn't make them poor TVs.