I think I understand what you are getting at, Megan_OS. You want the next opened window to open as full screen, or at least larger, when you right-click and choose "Open in New Window" yes? Some links automatically open into another window, but many will just open in another tab. Try making an IE window large, then close it. This should save the last known size of IE and so new IE windows will open at that size. You can try the same with having it maximised as well.
Also, IE6 and IE7 are not available for Windows 7. Windows 7 only comes with Internet Explorer 8, and can not use prior versions. However, IE8 does have a "compatability" mode where you can make pages render and react like older versions of IE. You can try that also. However be aware, that some sites (especially games) will purposely tell the browser to open another window of a certain size. IE (and most other browsers as well) will attempt to follow that request.
How is Window 7 working for you? Everything else good?