www.photoshop.com is being discontinued.
You may still be able to create an account and log in at http://www.photoshop.com. However, the site will soon be taken down and replaced by http://www.photoshopshowcase.com and http://www.adoberevel.com/, both of which are supported in version 11 of the program.
However, you may have some additional issues going on, since you're not even able to log on to the Adobe site at http://get2.adobe.com/flashplayer/ .
My guess is that you haven't got all the latest Windows 8 updates. Go manually to Windows Update and ensure that you have selected the option to Show Hidden Updates. Then make sure you have these non-critical updates installed in addition to those that install automatically.
Also ensure that you have the latest version of Quicktime, per the program's requirements.
Windows 8 is still sort of a work in progress, and it still has a number of issues with a number or programs. But if you can't even navigate to a major web site, there may be some things you need to do on a more fundamental level to the operating system.
The links that Steve provides above, will be the places to ask all questions, regarding the migration from Photoshop.Com to Adobe Revel.
There are a lot of useful discussions and FAQ's, that will answer most questions. If the answers are not there already, then a post to the Discussions forum for Revel, will yield direct answers.