IN Android 4.0.x (Ice Cream Sandwich) the factory reset may be under settings --> Backup & Restore. just choose the settings reset option, which *should* leave your data (photos, music etc.) untouched.
If that doesn't work, we need more information in order to help you. please register on the forum (we're very helpful) and post in the sub-forum for your phone, or re-post as a guest, giving us the make & model of phone, your carrier (Virgin, Verizon or whoever) and which version of Android your phone has (2.3 - Gingerbread, 4.0 - Ice Cream Sandwich or 4.2/4.3 - Jelly Bean)