Android phone just wont stop?

im about fed up with my phone. whats the point if the phone is just going to lag and freeze? its running tons of apps in the background. and every site tells me to use a task killer so i try and yea that works Great for a second. i click the widget and it says "15 apps killed" then i wait 60 seconds and hit it again and boom "11 apps killed" why were 11 apps running?????? i didn't open any apps.... For example, i have never once opened the Uno game app but android has it open every time i check the task manager. WHY? i want to show off my phone and its really embarrassing when i lean over to show someone something and i click a button and nothing happens cause its already running 20 apps all by itself!? that's just not cool. is the phone playing Uno when im not using it? i know its a "smart" phone and that's great but i don't want it doing its own stuff unless i tell it to. I would just like to be in control of my own phone. its basically a little computer and i would NEVER stand for my computer to be randomly running tasks without me allowing it to. so yea the task killers do kill the apps but then they just immediately start running again. And while i'm on the subject.... people either swear by their app killers OR they say omg app killers are the worst thing you can use on an android. If i cant use a task killer then what am i supposed to do? i like playing games on my phone so i have to first kill all the apps then wait a min and kill the apps again and then start the game and IF the games not slow yet i have about 2 min before the game becomes un playable and i have to exit and kill 20 apps. Please, what am i supposed to do.