//1
Image img = Image.FromFile(path);
//2
pictureBox1.Image = Image.FromFile(path);
//

public Image GetImage(string path)
{
   FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read);
   Image result = Image.FromStream(fs);          
   fs.Close();
   return result;
} 
//1
Image img = GetImage(path);
//2
pictureBox1.Image = GetImage(path);