Minecraft

I know this isn't a place to ask help here but i was wondering if anybody knew how to fix my problem ,
i would in include pictures but... what can i say... this shit dose not work, i have purchased the game made a account But when i download the exe to download the game, Nup . nothing pops up mostly and a java icon just sits inthe task bar " running" and lagging my computer, 2 times it had poped up reveling a mine-craft login ? i think and its so laggy , and when i move it crates a black screen inside the popup ....

if you have any help please help me..
the "tec support there is not 1 bit helpful. ":(

haha thanks you ill try that and see if it works , ill reply later with the result