Featured Images for a Category Blogroll

Hi, I've created a blog page for a category ('news') for a website I've created (welshminestrust.org/news). I'd like each blogpost to show up with a small image to make the page more interesting but putting a featured image into the post adds a HUGE image to the blog page and it sits horribly above the title (as you can see). Putting the image in the post content doesn't show at all. Is there any way to get images to show below the blog title, but above the excerpt in a size that is more suitable to the size of the the page/content? Or something along the lines of a large thumbnail style image that sits to the left of both the title and the excerpt? Thanks.