Trouble viewing options in Outlook express

for some reason ,a setting or something has been changed that i cant seem to find.before when i double clicked on a email it would open up maximzed without the toolbar header.now(i have my current view with emails on the top half and bottom half with the opened up email) when i double click on a email it opens at the bottom in a new window with a toolbar header.basically trying to get my emails to open maximzed when i double click.sorry if i sound alittle lost,cause i am.lol.thanks up front for any help.peace

 

Click on view, layout, uncheck, "preview pane "..