If i was really unsure what to do i would also ask Karma IT he knows what hes doing.

A basic cleanup would work well enough really.

defrag
stop all your startup programs except maybe antivirus and steam
uninstall all the shit you don't use
virus scan etc.

Yeah defraging the is the best way IMO.

Plus remove anything that you DONT need in your hardrive.

I don't know what version of window's you have, but if you've done what people have advised i.e. defrag or clean installation of windows, there are also various OS tweaks you might also wanna try (i.e by turning off windows tasks that you don't use or need):

WINDOWS 7
www.blackviper.com/2010/12/17/black-vipers-windows-7-service-pack-1-service-configurations/

WINDOWS XP

www.blackviper.com/2008/05/19/black-vipers-windows-xp-x86-32-bit-service-pack-3-service-configurations/

www.blackviper.com/2008/06/26/black-vipers-windows-xp-pro-x64-64-bit-service-pack-2-service-configurations/

WINDOWS VISTA

www.blackviper.com/2009/05/31/black-vipers-windows-vista-service-pack-2-service-configurations/

Thanks dude, im trying that now, also I did defrag my computer and CCLEANER but yeah its still a bit sluggish, it might be my Power supply cannot handle the quad core or the graphics card..

your computer will just stop if that's the case