Sorry that you are still having this issue. There are many Microsoft programs of course and also some 3rd party programs that automatically associate themselves with Internet Explorer even if another browser is set as the default. When these are used this sometimes will trigger IE because it is associated with that program. I don't know your internet provider but even some of those are set up to use IE if they provided you software for their connections.
Did Internet Explorer 7 come preinstalled with your system or did you upgrade to it later? If it did not come with the system but it came with IE 6 you might try uninstalling IE 7 then you might try uninstalling IE 7 which would roll it back to IE 6 and then download a new copy of IE 7 and install it. Even if you don't use it regularly you should update to IE 7 as it is much more secure than IE 6. Plus you do have to use IE occasionally in order to get Windows updates. Now if the computer came with IE 7 you won't be able to do this.
I see that you run The Weather Channel on your desktop. This may be associated with Internet Explorer, even though it may not look like it. It IS running all the time it appears, you might either stop this from running all the time or if you no longer use it then uninstall it.
Also running is this service TomTomHOMEService, this may also be associated with Internet Explorer. This service runs at start up. It isn't required. You can try stopping this auto start by going to Control Panel -> System and Maintenance -> Administrative Tools -> Services. When this opens scroll down to TomTomHOMEService, double click to open it's properties and change start up type to manual if you use this often, if you no longer use it then change the start up type to disabled.
You can set the default browser On Windows Vista and above, this feature is renamed "Set Program Access and Computer Defaults" and can be used to change the default for all users of the computer, if you are logged into Windows as an administrator.
You can also do the following:
You can manually set the default browser by selecting it as the the default program for individual file types and protocols, as follows:
Click the Start button, open "Default Programs" and then click "Associate a file type or protocol with a program".
Assign the following protocols and file types to the browser you wish to set as default:
* URL:HyperText Transfer Protocol (HTTP protocol)
* URL:HyperText Transfer Protocol with Privacy (HTTPS protocol)
* URL:File Transfer Protocol {FTP protocol)
* HTML File
* HTM File (optional)
Finally Force Firefox to make itself the default
If Firefox already thinks that it is default, exit Firefox completely, go to "Start Menu -> Run" and enter this into the text box:
firefox.exe -silent -setDefaultBrowser