I tried to install the image i got off of Torrent, which is supposed to be from a 40GB drive, onto a 40GB drive. It wouldn't expand

It didn't work because of the swap size. I was trying to go with a large swap because I knew I'd be adding the 160GB disk later. However, if you are staying with a 40GB drive, you should be fine by just decreasing the swap. This is described in the middle of step 6 of the how-to.