PC No Longer Picking Up Connection Via Ethernet Cable

For other three years, me and my brother have both been connected to our router via ethernet cables. On this Tuesday just gone, however, my brother took it upon himself to mess with the router whilst I was out. Apparently, his internet had been down since we'd had a power-cut on the Sunday, (My internet was fine, and always has been and was fully functional after said power-cut), and before then, it'd been going really slow, and sometimes cutting out. Okay, no problem. Now, the the thing is, that morning, I was on my internet, all happy, and when I returned home that evening, my PC wouldn't connect. My PC still refuses to connect, three days on. It's not even picking up that there's something plugged in.the router is actually flashing to say that my PC is plugged in and connected to the router. I know that there is nothing wrong with the modem or what have you, as I linked my laptop up to my PC via a cable earlier today to try and get it online. It's not a virus program problem, either. Like I said, it was working Tuesday morning, nine hours later, I come home, my brother restarted/unplugged the router, and now my PC won't connect. I should also note that he's now had to go wireless via a dongle, and everyone else in the house uses wireless laptops. I can't connect my PC to the internet with a dongle

Microsoft Windows [Version 6.1.7600]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.
C:Windowssystem32>ipconfig/all

Windows IP Configuration

Host Name . . . . . . . . . . . . : PY110
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No

[code]....