Acer Aspire 57327, Intel 2.2GHz dual core, 3gb RAM, 250gb HDD. Wiped Windows 7 off and installed Ubuntu 12.10

I've installed Ubuntu 12.10 for the first time. I faced an issue with no backlight during the installation process, so I had to hook it up to an external monitor thinking I'd be able to resolve the issue after the installation. Now Ubuntu is working fine on the laptop, but I still face the no backlight issue without the external monitor.
I'm a complete novice when it comes to Linux, only ever using Windows, and I'm starting to stress out.

I've found a post here on the exact problem I'm facing, though when on the startup screen where I'm asked what to boot (I believe this is GRUB2?) I can only press enter for any of the options, or 'e' to edit something. Therefore, I have no idea how to follow the instructions for the fix. Whilst I'm decent with computers, I feel completely lost trying to fix this issue, especially when every 'solution' assumes you have some knowledge of how the OS works.

Also, some of my keys (ESC, F1-12, fn, etc) don't work, so I'm using an external keyboard without any brightness options (like an fn key to change brightness)