I've been having internet problems for about 2 months now. At first i thought it would pass after a while, and after that my dad said he'd fix it i waited for him not to do anything for 6 weeks, and now im seeking knowledge from MMO-champion.

Here is a description of the problem(s):

The internet will be totally gone. No devices can connect to it and when you troubleshoot via Windows 7 it tells me to unplug the device, then wait 10 seconds before i put it in again.
This "blackout" can happen every 15 minutes, uto every 4 hours or so, and im starting to believe that its connected to how many devices use the internet at the same time, because it seems that when im alone, it mostly works fine. Another idea can be that its bad whenever many people in the neighborhood is connected at the same time. Not the same network ofcourse, but it might still affect it.

Another problem is that it also randomly disconnects for 5-10 seconds every now and then. This is not that big a deal, but it does require me to log in again to WoW, and when playing Magicka multiplayer, you are not allowed back into the game after a DC afaik.

An interresting fact about my problems is the icons for connection.
Sometimes it gives me the squared monitor thingy, and sometimes the 5 bars (2 or 3 normally filled) When im having problems the red triangle with an exclamation mark comes over it, and if im seeing the bars, i know that its a minor DC, but if i see the square+triangle, its a blackout.

I do not know much about computers, and neither do i know much about network etc, but here is a brief description of my "setup"

I sit in the basement with my computer. an Ethernet cable (i think) goes out from it, into a box with an antenna on it (router?). Upstairs, behind the TV, we have a modem, or 2 boxes with cables etc wired into them. These are the ones im told to unplug for 10 sec every blackout.

My father has only come to the thought that the internet collapses when it gets overused. This can be through, since its weak when many people are home, and it is weaker when i play WoW or talk on skype.

If anyone has any clue what my problem might be, or have any suggestions on how to improve my connection please help.
If my descriptions are not accurate enough, inform me on what i need to find out, and i'll do so.

And as a side question, is there a program to monitor your current internet connection strength?