You don't have to; use the Picturebox control. Load your bitmap into it and use either the internal Pset and Point functions, or the faster GetPixel and SetPixelV API functions. Converting to grayscale is also easy. Some say that you can just add the red, green, and blue channels but it isn't that easy; you need to weight each differently.

I suggest looking up all of these, and soon you'll be ready to .SavePicture your bitmap to the disk!

If you need an example, message me.