If your router also acts as your firewall, then it usually has a section called "Logs". You might have to enable it, it's not always enabled by default. You might also need to mess a bit with the logging level (how verbose/detailed you want the logging to be).

It's strange that your father is using it and has no problems, but you said that you had problems while surfing the net. Is your father using the same computer, or only the same router ? If it's the same computer, is there any one particular application that you always (or most of the time) will be running, but not your dad ?

Is it _always_ the case that you can't send messages, but you can receive them ? Or is it both ? I'm trying to figure out if it could be that your router, for whatever reasons, is dropping packets - that should usually be both incoming and outgoing. I can't think of a reason why it would become overloaded just one way (I don't think that even extensive packet filtering rules can slow a router for a home network that much...).

Is for some reason your home network really overloaded ? Are you connected to your router via a wireless link ?

Sorry, I don't have any specific solutions.