One image stretched; one didn't?

Sorry @cherylweb27, I didn’t see this post for a month! Must have slipped through my filters.

For the first image:

If the post-thumbnail does not have a specific crop defined, PTE won’t set an aspect ratio for you, and wordpress will allow you to have any aspect ratio you want as long as the height or width is respected (depends on how the post-thumbnail is defined). This is the case for the stock medium and large wordpress post-thumbnails. There is a setting to make the thumbnail size cropped on the Media settings page.

If you want to have a certain aspect ratio respected you can set it under the options menu when you are cropping the post-thumbnail. (Sorry for the maths, but you have to put the value in as the result of width/height).

For the second image:

Usually what happens when an image gets grainy is that you’re cropping a small image into a bigger post-thumbnail. I thought that I told PTE to display a warning if this was going to occur, but perhaps it’s not working correctly anymore. (Edit: after looking at the page you pointed to, it looks like the portion of the image you are cropping is much smaller than the post-thumbnail size that you want, resulting in the grainyness, try cropping a larger area).

In some cases the wordpress code that does the cropping could be using a quality level that’s too low (only for JPG’s), which you can change at Settings → Post Thumbnail Editor (set it at 100 for highest quality).