What we perceive as light is a form of radiation, so for a monitor to be of any use, it has to give off some sort of radiation.
If you're worried about HARMFUL forms of radiation, the levels of radiation put out by even CRT monitors is very low. If you're sitting within about a foot of the monitor for prolonged periods of time, in years, then you might have some ill effects, but mostly from eye strain.
There are plenty of good reasons to switch to an LCD from a CRT, such as lower energy consumption and lower consumption of real-estate on your desk, but radiation concerns isn't one of them.
I heard that crt monitors give off radiation, so im thinking about switching to an lcd. So should i buy a crt or lcd monitor?