When you say 'make the photos bigger' - do you mean you want them to be larger in your original post?
Because - and I may very well be telling you something you already know
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, but just in case: when you post, you have the option of small, medium, or large, AND
- once published, if someone clicks on the photo, it will open to its original size.
As far as sites, a few friends of mine are on
Square Space, though not free, but does offer a free trial period, and I think you can make it your own url.
Lastly, for photo storage - I use photobucket and am very happy with it, but with Blogger, I upload directly from my computer (which I think helps show the original picture size when it's clicked on).