Excel 2007 versus 2010 VBA message boxes and Dialog boxes look different

I work with the same spreadsheet using Excel 2010 at work, but at home I use Excel 2007. A couple of days ago, I noticed that my VBA message boxes when using Excel 2007 look different than they look when using Excel 2010. In Excel 2010, they have a "blue fill" on the title bar and the "?" and "X" characters have actual buttons. In Excel 2007, the title bar has "no fill" at all and the "?" and "X" characters have "no demarcations" around them. Because of this, I began testing other things between Excel 2007 and 2010. I also found that in 2007, after right clicking in a cell and choosing "format cells", the same type of box appears (i.e., "no fill" at all on the title bar). When I do the same thing in 2010, the "blue fill" on the title bar and "X" character buttons appear. I am concerned because I am wondering if my Excel 2007 program has gotten corrupted. Please Help!

Thank you rorya. I will investigate that angle.