The grid defaults the row height to 17. It is not set based on the default font. But I think you can use code like this to set the default row height based on font height.
Font f = this.gridDataBoundGrid1.BaseStylesMap["Standard"].StyleInfo.GdipFont;
using(Graphics g = this.gridDataBoundGrid1.CreateGraphics())
{
float height = 5 + f.GetHeight(g.DpiY);
this.gridDataBoundGrid1.DefaultRowHeight = (int) height;
}