2 ques. Switch focus on buttons when user presses tab? Dialog box is transparent?

2 questions.
I want my program to switch the focus on buttons and edit boxes when the user presses tab. How Do I do this?

I created a dialog box and I see the text and the buttons in it, but the surroundings of it are transparent. This is my resource file:

OOC DIALOG 100, 100, 182, 71
STYLE DS_MODALFRAME | WS_POPUP | WS_VISIBLE | WS_CAPTION | WS_SYSMENU
CAPTION "Create New Or Overwrite?"
FONT 8, "MS Sans Serif"
BEGIN
CTEXT "Text", 100, 0, 0, 100, 30
GROUPBOX "", ID_SOME, 111, 111, 95, 48, WS_TABSTOP
DEFPUSHBUTTON "&Overwrite", ID_OV, 112, 6, 64, 14
PUSHBUTTON "&Create New", ID_CR, 112, 21, 64, 14
END