I looked in the Task Manager processes list and see that some of the basic programs are listed twice, or using excessive amounts of RAM, like svhost using 64K. I looked up all the items I didn't recognise (unfortunately I'm not too familiar with the list on my relatively new PC, so I'm not sure if anything doesn't belong) but of all the items I didn't know the only one I can identify as possibly problematic is atkkbservice.exe.
So, basically I'm screwed. I'm totally perplexed as to how simply connecting to a router could cause this kind of problem, and obviously I have very few options for dealing with it. Thank god we go the internet working on the laptop so I can come here and ask for help. Please give me any help or advice you have, as my PC is worthless right now.