Some new to gtkmm questions

[John Taber <jtaber johntaber net>]

3 questions so far: 

1) themes - is there a way to specify themes at the start of the program?  My 
dialogs look pretty plain or ugly right now and it would be nice to see 
something like plastik

2) splash screen - I have a splashscreen class that runs fine by itself but 
how do I specify it in "main.cpp"  so that after it disappears, main runs the 
main layout dialog.  my main now looks like:
int main(....)
Gtk::Main kit(...)
SplashDialog *splash = new SplashDialog();
splash->show();
delete splash;
MainDialog mainDlg;
Gtk::Main::run(mainDlg);
run(mainDlg)

with this the splashscreen never appears - do I somehow need to set it modal ?

3) displaying images - what is the best method for displaying images?  
Obviously button has a method to display a pixbuf.  But what if it isn't a 
button ?  Do I need to use a drawarea and render the pixbuf ?  Is there a 
simpler way like using a label widget?  

thks 
john