The amount of radiation emitted from an L.E.D. monitor is so small that it won't bother you. The glasses aren't needed, and really wouldn't help that much anyway.
Cover it in lead
A computer monitor screen cover will provde some protection.
There are glasses prescribed specifically for people who work on computers. The need manifests itself because the "reading" section on glasses is often too close for the computer, and the "distance" section often too far. I wear glasses with a third section between the "reading" and "distance" sections, and I call this the "computer monitor" section. I have heard this type of glasses being called "trifocals."
To answer your question it is not the computer to be worried about but the monitor, a large monitor creates more radiation than a small one so in theory a laptop would be the best choice if you are worried about radiation, but i have been around computers my entire life and i am just fine. one x ray is equivalent to 2-5years of computer usage depending on what type of x ray you take. These days, monitors do not produce x-ray radiation, because they are all LCD and not CRTs. In fact I would be surprised if even a huge CRT monitor produced the same amount of x-rays as indicated in the previous paragraph. Generally when the scare-mongers are talking about computer radiation they are talking about radio waves, and computers are no worse for this than any other electronic equipment. Mobile phones are orders of magnitude worse of course. Radiation from computers is nothing to worry about.
how is the first computer monitor
Video slot machines will give off some radiation, much like your TV or the CRT monitor of your old computer; however, none of them are likely to produce enough radiation to cause any sort of damage.
A computer monitor is hardware. It only provides for display.
Monitor is not plugged in or monitor is not plugged in to computer
Yes. All forms of light are radiation including radio and microwaves. Since a computer monitor releases light, it releases radiation. Note that most radiation is harmless because it is absorbed by the elements in the air and/or can't penetrate our skin. Only radiation emitted from highly energetic fission and fusion reactions or the radioactive decay of extremely heavy elements is harmful.
CRT
Video slot machines will give off some radiation, much like your TV or the CRT monitor of your old computer; however, none of them are likely to produce enough radiation to cause any sort of damage.
Your tower is your computer. If you are asking if the monitor and computer have to match the answer is no. You can use any monitor with any computer.