Okay so this is what I've been using the past year or so:

I can barely browse the web without it constantly lagging/ freezing.
Most games can't even run on it..
I am really uneducated when it comes to this type of thing, even though i spend a huge amount of my time gaming!
I just want something I can stream videos on, play games at a decent quality without lag/ glitchyness, ect.. nothing flashy/ fancy!
Some of the questions I didn't know how to answer simply because I'm dumb so please spoonfeed.
Budget: $300
More specific use (what games, what programs): League of Legends, Runescape, P.O.E, WoW, HotS
Planned time until purchase: 2 weeks
Do you need an Operating System?: umm? idk?
Do you have any specific preferred components?: as stated i know nothing about this
Do you need a sound or wireless card?: idk?
Do you want stock cooling or do you plan on overclocking?: idk?
Do you need a monitor? mouse? keyboard?: not unless i can just use the current ones i have
Zip code/location? (Shipping costs): 56601/ MN