|Why "I download movies, games, and tv stuff" if not a gamer?|
Why "I also have in my computer Corsair (CWCH60) Hydro Series H60 High Performance CPU Cooler" with decent CPU, basic video card and simple needs?
Why a GA-Z68AP-D3 for such basic needs?
Why Windows 7 Ultimate for such basic needs?
Why "As for RAM i got 8.0 GB" for such basic needs?
You did not need a Z68 motherboard but there is nothing wrong with the choice and it offers you a variety of choices for later.
You should have saved on Ultimate and stayed with Home Premium.
You should have saved and stayed with the stock cooler.
You should have saved and stayed with 4GB of memory but there is nothing wrong otherwise with 8GB.
You should have spent a bit more and purchased a decent graphics card.
You might need a better hard drive, but you did not mention what you had, BUT your problem probably stems form your internet or you are lax with your system maintenance and your system needs a good cleaning out.
What antivirus program are you using? If you have Norton or McAfee, dump it and replace it with Avast Free version, it will not bog down your system the same way.
On a system with a Core 2 Duo, 4GB RAM, a GTS9600 Graphics, my daughter will simultaneously have open as many as 15 web pages, upload text and pictures, download image files, work on images on GIMP & SketchUP, six to eight notepads with text, at least 2 stories open in OpenOffice, and more, before she complains about slowing down and I have to tell her to begin closing things
Either you are not telling us the whole truth about your system and what you are doing on it, or you are doing something vastly wrong. As mentioned, the only weakness is your graphics, probably your internet, and possibly your antivirus program.
You have to be a little bit crazy to keep you from going insane.