CRT displays colors and especially black better than LCD. (With LCD, it's actually a gray) For movement, CRT will display everything very well with no blur. You can look at a CRT screen from any angle and it will be visible, not so with LCD. You can also have higher refresh rates to reduce eye strain. My 19" CRT monitor has never caused me any eyestrain because I have the colors and brightness soft (as they would be by default on an LCD monitor..because everything is dulled) and my monitor was designed to be used for continuous usage (It was a high end monitor at the time with higher refresh rates at higher resolutions and a lower dot pitch, which comes standard nowadays - refresh rate is how fast the screen blinks, dot pitch is the thickness of the grid that is on the outside of the monitors). My refresh rate is set higher, which is something LCD monitors have poor rates for.
It isn't the radiation that causes your eye strain. It's mainly the refresh rate and the softness of the monitor.
I suggest you go with CRT and then set it up properly for long-term use if you're going to sit in front of it for hours upon hours at a time and you don't mind having a bigger, bulkier monitor. It will save you some money and you will get better performance out of it than any LCD (movies and games will be more crisp and clear, shadows will look more like shadows, etc, etc). You can get a 19" CRT for less than a 15" LCD.. If you need help with this, I'll be more than willing to show you how to do it. It's an easy thing to do that most people seem to be unaware of.