i apologize in advance for the dumb question. i have a iphone 3g on 3.0, 4.26 BB. it takes forever to back up my phone on itunes, if i update to 3.1.2 with a custom firmware, will it restore my phone and erase all of my contacts and info?
If iTunes is taking forever to backup, perhaps you have a corrupt backup. In iTunes Preferences, click on the "Device" tab, select all backups, and click "Delete Backup." After that, do the backup again. It might still take a while, but should do it in less than "forever."