all of us here in the USA use/prefer 29.97/30fps 23/25 looks too choppy in comparison on our monitors
All of us? Everyone in Hollywood prefers 24fps of course… oh and the makers of all those big HBO TV productions also shoot at 24fps. I’d bet that most high end commercials are also shot at 24fps in the US too. There are some feature films now being shot with a much higher frame rate, but they seem to have been met with mixed feeling. It’s hard to say whether the association of higher frame rates with cheap production is learned or if there’s something inherent.
But the rule is that 24fps tends to look classy like a feature film, whereas 29.97fps and any interlaced format (i.e. NTSC 59.94Hz or PAL 50Hz) tends to feel rather cheaper like video.
When feature films are screened on US TV, they use a 3:2 pulldown and disperse 23.98 frames of film per second over 59.94 fields of TV per second using an uneven cadence (some frames cover three fields, others cover only two - as a US viewer you’ll be used to it and won’t generally notice, unless there’s a very smooth, fast camera move)
The transfer of film to PAL is rather higher quality in that one picture covers exactly two fields (running at 50 fields per second) and the picture cadence is completely accurate. However, since 25 doesn’t divide into 24, films transfered to PAL are generally 4% shorter.
The varying frame rates were originally based on the frequency of the alternating current - that’s why Euro-TV runs at 50Hz and US TV close to 60Hz. NTSC reduced the field frequency to 59.94Hz later with the introduction of colour, to stop the color carrier signal interfering with the sound carrier signal and making interference patterns on the screen.
In summation: NTSC 29.97fps is for the US, Japan, most of south America. PAL 25fps is for Europe, India, China, Russia, Brazil, Argentina, Uruguay. Film 24fps is universal.
TV Standard by country (SECAM is a 25fps 576/1080 line system very similar to PAL)
(incidentally, 23.98 is the frame rate that film is slowed down to to exactly fit the frame rate of NTSC TV using a 3:2 pulldown - any editor needing to insert 24fps material into an NTSC timeline will know how to deal with this, so best to use a nice round 24 and not scare anyone off! )