Minecraft graphic issue

Ive had this issue sence I got the game back in 1.2.8 I think, and I never bothered to report it. Ive searched it, and I can not find it anywhere... I have these giant lines/squares that cut off my vision depending on which way I face, and it changes all the time... Also my signs and chests turn with my screen, and are blue. One more thing, mobs are only shown about half the time I load up the game, and when they do show, about an hour or so later, they disappear... pictures bellow