Windows doesnt start...:(

OK Here's the story:

This morning I was trying to get a program to work, and it wasn't. I found out I needed to change the system language to Japanese to do so. So i changed the system locale to Japanese.. and restarted my computer.

Windows wouldn't start. It would reach up to the windows logo for a split second and then go to a new screen that would prompt me to either start windows again normally or go to system recovery.

So I did, I went to system recovery and I tried to do system restore, It almost worked but at the end it gave me an error saying there might be a problem with an anti virus (I use Avira anti virus free edition)

Annnnd, i'm stuck here... I tried to see if i could use command prompt to access the control panel to change the system locale back to english, but I cant access control panel through command prompt from the system recovery options.

Any help would be very much appreciated.. I've been trying non stop to do whatever I can but I'm not too computer savvy Please don't tell me my only option is to reformat... I dont even have my windows 7 disk..

I just fixed the problem.. I feel dumb for not trying it. Here's what I did if it helps anybody else on a problem like this or similar to it :

When you hold F8 at startup and get to the advanced boot options, go down and press enter on "Last known good configuration"

I was stupid... Did so much unnecessary stuff such as burning a recovery disk onto the flash drive, trying to get system repair to work, etc, etc.. It was all so simple. Thank god.