but not enough space to describe everything. So here's a very condensed summary:
1. Work out how much storage capacity you actually need. Uploading phot's is one thing , but the size of the pictures is another thing altogether
2. How much bandwidth do you need? I.e. how much data will be downloaded from your site each month?
3. Do you need a dedicated IP address?
4. Do you need email addresses included? If so how many?
5. Not so sure on security. If you're storng / distributing sensitive information then you need to go to a specialist supplier. If not then don't worry about it.
6. What other server support do you need (e.g. php, mySQL etc)?
All this will define what kind of package is best for you.....