You can download your pictures from Photos and then they'd show on your Gallery. But that would mean your pictures would be in your device, so that would take up space.
As for texts, if you had an iPhone before, you need to deactivate your iMessage account from that number. If you still have issues, you need to ask your iContacts to turn off iMessage for your contact on their iPhones (that way it'd force the iPhone to use SMS for texting and not iMessage).