[redhead]

As your DoMenu() is made now, it looks like:

USHORT DoMenu()
{
  USHORT choice;
    cout <<"\n\n***Menu*** \n";
    cout <<"(1) Draw Your Rectangle\n";
    cout <<"(2) Area\n";
    cout <<"(3) Perimeter\n";
    cout <<"(4) Resize\n";
    cout <<"(5) Quit\n";

 cin >> choice;
 return choice;
}

If you wan't to be sure, it only returns with an integer within the 1 - 5 selection, then make it:

USHORT DoMenu()
{
  USHORT choice = 0;
   while(choice < 1 || choice > 5)
   {
      cout <<"\n\n***Menu*** \n";
      cout <<"(1) Draw Your Rectangle\n";
      cout <<"(2) Area\n";
      cout <<"(3) Perimeter\n";
      cout <<"(4) Resize\n";
      cout <<"(5) Quit\n";
      cin >> choice;
      if(choice < 1 || choice > 5)
          cout << "Sorry your choice of (" << choice
                  << ") is not within the required limit."<<endl
   }
 return choice;
}

Note the above has not been testet..