After this the problems started, I ended up unable to connect to the Linksys or the Netgear Cable Modem (In router mode or Modem mode) via ethernet. Other devices could connect wirelessly to both the Linksys Router and the Netgear Modem (when in router mode), and I asked a few people what the problem could be & it was suggested that I disable IPv6 in the ethernet adapter properties, I did and was able to get an IP through DHCP rather than manually entering IP, subnet etc.
However that was not the end of my problems. Once I got connected to either the Netgear modem or Linksys router, the Internet connection is very unstable, web pages started coming up with corrupted images or come up as nonsense text, certain Adobe Flash "movies" would also fail to load (such as the speed checker on speedtest.net). Eventually I cleared both IE & Firefox cache as well as flushing the DNS cache, this seemed to help significantly with corrupted images & flash objects and websites now rarely have corrupted text. However YouTube videos start playing then skip ahead and go to green or black screens instead of the actual video, and the speed tester on speedtest.net now does not complete the download test & progress to the upload test if the download speed is more than about 5Mb/s.
I have also found that downloads of any size won't complete, either they don't start downloading or they stop at ~90-99%. If they do complete they are often corrupted. I also use Steam for gaming & the Steam news images were corrupted & game updates took ages to complete because they would start and stop. Normal web browsing seems to work ok, I can access Facebook and Twitter ok without corruptions etc.
One of the devices I connected was a Windows 7 Home Premium 64bit Laptop, this connects just fine to both the Netgear and the Linksys Router without me having to disable IPv6 in the adapter properties, it also runs the same version of IE, Firefox & Adobe Flash and has no problems playing YouTube videos or doing a speedtest on speedtest.net. I have also tried an old Acer laptop with Vista Home Premium on the ethernet directly to the Netgear cable modem & it too works fine.
I use Norton Internet Security as my antivirus & I have done a full system scan with nothing found, I will scan with MBAM in an hour once I get home, and I am considering running a couple of preboot virus scans just to ensure it isn't virus related.
I am at a loss as to what to do now so I would very much appreciate some assistance.