I've recently used Fontswap to change my iphone's system fonts. After making this change, none of my apps would start up so I attempted to reboot my iphone. Now my phone is stuck at the apple logo boot screen. I have tried rebooting several times with no success. I have not installed SSH and can't attempt to undo whatever changes may have caused the issue. I could boot the iPhone up in DFU mode and use iTunes to restore it, but that would also update my phone's firmware and baseband to the latest versions rendering the yellowsn0w software unlock obsolete.

What options do I have? Can I roll back the updates after an iTunes restore? Can I access my iPhone's files through other means? Thanks in advance