Resize bitmaps

I want to resize a bitmap, but that seems to be easier said than done.

My original bitmap has pixel format 8bpp indexed.

I would think that creating a new bitmap with the constructor 
  Bitmap compressedImage = newBitmap( Image original, original.Width/2, orig
inal.Height/2 ) 
would do the trick, but it changes the format to 32 bpp Argb, even though it
 says in my book that 
"the new bitmap inherits the pixel format of the existing bitmap".

So, I thought I could clone my compressedImage:
  Bitmap cloneCompressedImage = compressedImage.Clone( new Rectangle( 0,0,co
mpressedImage.Width,compressedImage.Height), 
  System.Drawing.Imaging.PixelFormat.Format8bppIndexed ) ;
but it raises an OutOfMemory exception, no matter which values I try for wid
th and height.

Just for fun I tried to clone my original image:
  Bitmap cloneOriginalImage = original.Clone( new Rectangle( 0,0,original.Wi
dth,original.Height),
  System.Drawing.Imaging.PixelFormat.Format8bppIndexed ) ;			            
It works fine, but if I try to set the correct dimensions I get only a porti
on of the original(of course).

I've also tried using
  Graphics gr = Graphics.FromImage( original );
but got an exeption saying "A Graphics object cannot be created from an imag
e that has an indexed pixel format"


If anyone has an idea on how to maintain the pixel format, or maybe has anot
her way of doing this, - please let me know!