Some advice, perhaps?

[Silver]

From those of you who understand computers much better than I do.

For the average person, when downloading something (a movie or even windows updates) the game experiences high ping.

I seem to have high ping (and by high ping I do not mean 300ms like some people complain about. Mine usually never drops below 1000ms and usually hovers around 2400ms) when there is nothing else running except the game, but then my ping lowers to what I consider normal (300ms) when I download something.

I was wondering if anyone could explain what is happening with my computer and/or internet connection and if it could be explained what I should do in order to ensure my game always has low ping.

For one thing, I have no way of directly connecting via ethernet. I can only use wifi, though my connection is five bars strong and technically wifi should not be an issue from what I have read. The internet is not mine, but a friend's, and other people also use the connection (I'm thinking this is the problem, though I am not entirely certain).

Any advice would be appreciated.
Thank you.