Are you sure your pics aren't on the sdcard (typical)? Because a factory reset won't erase the card's contents plus you could remove the card and use a card reader to access them. If they are in fact on the internal storage, you could try wiping cache in the stock recovery (if stock) in hopes to get the phone booting further. To do that, with phone powered down, hold home button + volume up + power button. When you see the "recovery" splash on the screen release only the power button and keep holding the other two. Once at recovery, choose option to wipe cache. Worth a shot before doing a full blown factory reset.
If you happen to be rooted with a custom recovery, you can boot into your recovery and use adb to pull media from the internal storage as recovery will likely work even when the OS is not booting and custom recoveries include the ability to run an adb daemon.
