Just to give you an example a friend of mine works from home and at about 2 pm every day his laptop would start to have all sorts of connectivity issues with the web. The end result seemed to be that the fact he was heating his coffee in a microwave which was directly interfering with the wireless connection between the router and his laptop. The solution in this scenario was to use a different wireless channel on the router that did not seem to be effected by the microwave did not interfere with.

Ok enough of my rambling I would suggest that you check your Internet connection speed with a few on the online speed checkers is a a good start.
see how this speed check fairs up to what you isp says that they are providing. I would also suggest that you try this test a few times a day say in the morning, afternoon and late evening. this should give you a good idea how busy your isp is and at what times of the day

Good Luck
J