Many people are having problems with Windows 8.1 and IE 10. I'd suggest installing another wen browser to see if it helps. I personall use Chrome and have not had the problems mentioned by others. I think Chrome has a built-in version of Flash, which may be why it works better.
Note that there is no reason why you cannot have more than one brower. I need to keep my copy of IE as the default for other reasons, but I only use Chrome when accessing the Comcast web site or any site that does video streaming. Hope this helps.