Does your blog use HTML tags? That is, do you post pictures using < img src="picture.jpg" > ? If so, try < img src="picture.jpb" height = 300 >. You can also use width instead of height. Play around with the value until it looks good!
Yes, it uses html...
Ok. I'll mess around with it...
It looks like the maximum width of the pictures needs to be about 410 pixels to fit the layout. Try adding width="410" to the image tags.
Or you could open the photos in an image editor to size them down, and re-upload them.