Improve and Questions

Hi making some test on https://gtmetrix.com/, please can you tell me how to:

1. Set default image sizes for photos when they upload, now every photos get the size "large.jpg" i down know where to change that and resize all the photos to a desired size. thats will be good even when you view photo on the lighbox now is very slow: http://easysocial.stackideas.com/albums

2. Option to disable slide on over on the photo grid http://easysocial.stackideas.com/albums that feature loads a lots of photos and made that page slow, where is the option to disable that?

3. I want to know how can i display a upload form on a single page without the user module if you check http://easysocial.stackideas.com/albums/565-demo/albums/form the problem with that form is about the cover size and the form is not clear for users without experience, would be possible to add option to enable that feature via lighbox?

4. Photo Categories: As i can see there is no option to add photo or album categories, any option to have that? thats important for most of the communities our planning is to build a photo community but with that feature is impossible.