right click on the bottom panel / panel options / panel settings / more settings / maximise panel
I usually just copy the mail folders to a usb stick. Depending on your system they will be stored in your home folder - under 'mail' or as a hidden folder under 'kmail'. Also a good idea to copy your mail settings. These are stored in a hidden folder under your home directory .kde/share/config as:- emailidentaties & kmailrc
the easist way i found is to log-out and and then select kd4 and log back in. this will then make kd4 your default on future log-ins
Sorry but it has been a long time since I have used windows. Kmail can save mail in two formats - the first maildir which is no good for your purposes but the second way mbox might be of use. The mbox format can be used by mozilla thunderbird and I suspect outlook would be able to import mail from thunderbird. But please go into outlook first and see if the option to import mail from the mbox thunderbird format is available. If so you can create a new folder in kmail, change the default setting ...
you might want to give kshowmail a try:- http://www.kde-apps.org/content/search.php