An LCD should reduce the radiation quite a bit. I use a 19 inch StarLogic and its easy on the eyes, with clear and sharp details. I didn't have to break the bank for it either. For now, you might try turning your CRT monitor slightly to one side to minimize the direct stream of 'x-radiation' into your eyeballs.
Another thing you can do is increase your refresh rate. If your CRT monitor is set at 60hz, it can get pretty irritating after a while. You can change it in your display properties, settings, advanced, monitor tab. 75hz is a comfortable level on most CRT monitors.
Lastly you can always back off the contrast which will ease things a bit, especially if you are working with bright backgrounds such as word documents.