In older .net framework versions, calculating the height of a multi-line windows form label was not a straightforward task. I recently tripped acrossed a new technique available in the 2.0 framework for calculating the space that a label will occupy given its font and the runtime screen resolution, making this task easy.
using System.Windows.Forms
TextRenderer.MeasureText(IDeviceContext, String, Font, Size, TextFormatFlags);
Sample Use:
Label lbC;
TextRenderer.MeasureText((IDeviceContext)lbC.CreateGraphics(), lbC.Text, lbC.Font, lbC.Size, TextFormatFlags.WordBreak);