The screen doesn't work!

I found my mac in the basement after 5 year, the day after I try to turn it on and all go well. The day after I turn on it and I use it for 2 hour, I touched it and it was hot but not too hot, and after 1 hour i turn off it and I saw the screen all red, but I thought it was normal. After 3 hour I return on the mac and I saw the screen blu I didn't know what was happen to my mac and i turn it off and I return on, now the screen was green, I return off, return on now red and I turn it off for the fourth time. the day after I try to turn on it but the screen didn't work, it was black. What's happen to my mac? Can I fix it without change the CRT?

(Sorry if I did mistakes, I'm not an englishman)