I have a directory full of pictures how do i shrink them?

Have juse installed gd

Can anyone help me?

You mean to crop your images?

no want to make thumbnails

I'm sure GD has functions for image transformations like scaling and rotation. As such, I'ven't carried such work. I've also heard people use something called imagerick also, for the same purpose.

I've never attempted to use GD, but you should take a look at this:
http://phpthumb.sourceforge.net/
they have a ton of features, I love this script as it has a ton of useful features. I know this is not what you asked for but you can take a look at the source code (and if all else fails, just flat out use this script)

what would i use to make thumbnails?

using php that is