Windows Forms has never provided a really powerful re-locate/re-size on re-size model; but, in most applications you can achieve good results with using Dock, Padding, and Margin Properties (as Sergey suggests) on the ContainerControls (Panel, GroupBox, FlowLayoutTable, etc.), and the Margin and Anchor Properties on the Controls inside them.
Another alternative is to use a 3rd. party docking/tiling library like Weifen Luo's open-source (free) DockPanelSuite [
^].
In terms of a practical solution to your immediate problem, I suggest you follow Tim's suggestion, then test and see what doesn't look right visually, and try using Dock on the involved ContainerControls.
Worst case is you have to write some code in the Form/ContainerControl re-size Events.