You have a laptop with Windows Vista. Chrome was working well and now will not open. An only browser working normally is Firefox.
You haven't loaded new software or made any changes. Your Internet service provider is America Online and you have checked Windows firewall settings. You have made no major changes to your laptop.
You can try performing a Windows Vista system restore. Basically, you choose a date and time before your problem started occurring and restore Windows to that time frame. Open System Restore by clicking a Start button, clicking All Programs, clicking Accessories, clicking System Tools, and then clicking System Restore.
If you are prompted for an administrator password or confirmation, type a password or provide confirmation. Since you haven't made any major changes to your laptop you won't be losing any of those changes.