Chris,

I am not a VB guy so here is some C# showing how to set the DefaultValue attribute for Size.

[DefaultValue(typeof(System.Drawing.Size), "100, 45")]
public Size TestSize
{
   get { return _testSize; }
   set
   {
      _testSize = value;
   }
}

When you go into the property grid you will see that the value is 0, 0 - however, when you right click and reset it will show as 100, 45.

HTH
Neil