If I play games like ARK, minecraft etc etc on a 42 inch tv can?

Well I play games like ARK: Survival Elvolved - World of Warcraft - Skyrim etc etc and they're good games that come with amazing graphics and my computer is suppose to play them on medum-high graphics but can only play them on low because i get bad fps, is this because i play on a 42 inch tv? If i got a less big screen would i be able to play them on better graphics?

It is because your Video Graphics Card can't hand the graphics.
A larger screen will only make it look worse.