Probably 4k/60Hz. Next gen is still only maxing at 60 frames per second, so 120Hz is kinda useless for me since gaming is the only consideration for me buying one. IIRC, my current TV can do 120Hz or 240Hz. I shut that feature off because it didn't work well with my PS3. So even though my HDTV can do a high Hz rate, I have it doing 60Hz.
Oh, before I forget Paul. I needed the model number for the CRT so I can find the repair manual (it's starting to do some weird shit. Plus the geometry is very off and need to get into the service interface). It's KV-20FS100.