Okei so my INTERNET used to be really fast about two months ago or something like that, but lately it has been extremely unstable and slow. Its equally slow in every part of my house so its not the signals. We have had an EXPERT here that changed some cables because they were old, and that made the internet better for like 2 days before it went back to being bad again. I have been using http://www.speedtest.net/ and it tells me that my download speed is about 4 mbits and my uploadspeed is around 25. Please help me, im tired of lagging and dcing.

Where are your?
What are you paying?
What did your ISP say?
How many devices on your local network?
Have you TRIED to use only one device with Ethernet direct from the router?
Have you tried other speed tests?

With a speedtest.net result you're only sending tiny packets of data from one system to another. When you download a game from Steam etc. you're downloading a whole game (lots of bandwidth needed) from the source. The download speed can depend on the source and many other factors, not just your own download speed. Also the internet provider is mentioning for instance that you'll get CERTAIN MB speed, in reality you won't. That's why they mention 'upto xMB' so this way they can get away with PROVIDING much less. Try changing your service provider or upgrade t a different package. In some places in the USA you can get a sort=term Internet connection.
However, be prepared to pay about $80 for one month of broadband service.