Small "glitches" in system

Every 30 seconds my computer glitches. For example, I am typing this right now, and it takes about 3 seconds for the whole word to appear even though i wrote the word in 1 second.Also, I press backspace on my keyboard and about 4 seconds later it finally deletes the word. THIS IS NOT THE KEYBOARD. I HAVE USED OTHER KINDS ALREADY I was thinking of typing this under the "Games Section", because whenever i play "Halo" for PC, it slows down and glitches for a few seconds and is very frustrating. But, since it is happening also out side of games, I decided to post here. Hope you can help!.