Hi Hardlander,
OK, my guess is its a question of permissions in your browsers.
The site uses Java and Flash so you need those installed, if you don't have them, get them here...
http://www.java.com/en/download/index.jsphttp://www.adobe.com/products/flashplayer/It's not a Windows 7 thing (I use it myself) but in IE8 a couple of things don't display/work correctly so I agree with Glenn, Firefox is the best option.
The sign-in on the home page does work in Firefox, sign in then go click the 'All Pilots' button. You should see the amount of personal money/fuel you have and a box to buy/sell more. The sign in doesn't change (still asks you to login, but that will be fixed soon.
If you don't already, try running your browser as administrator, that might help.
It's a seperat login for the forums, but that obviously works for you as you can post here.
Hope that helps a bit,