Windows will not start, goes straight to startup repair

I changed explorer.dll in Windows 7. Then explorer wouldn't start when I tried to do so from task manager. So I tried to reboot. After also being unable to make headway in safe mode (using msconfig), as that also requires explorer, I launched startup repair using my windows 7 CD. Then after it said that it would reboot and fix any additional problems, it has kept rebooting and failing. I can't get to safe mode using f8 either, it just comes up with boot options 'Boot from CD' and 'Boot from HDD'.
Any help will be appreciated. If I can get out of startup repair, that would be tremendous. At least then I can activate word from task manager and save my coursework!
I'm going to try using Ubuntu's explorer to change the files back. I'll post back any progress! I'll be checking this wall at least 5 times a day until a solution is found.

Godspeed you wonderful people!

TVeblen said:

Hello Chrissyboy101. Welcome to the Forum.

Did you try selecting "System Restore" from the options when you boot from the DVD?

Yeah, it errors out with 0x800700b7
Thanks for the quick reply though!

'You must be logged into Windows 7 in a administrator account to be able to do a repair install.'
Nice idea, unfortunately it seems you need to have a working computer to be able to repair your computer. That seems to me like a paradox! :S
I'm using ubuntu to back up my C drive, now I'm thinking about getting an SSD and making the most of a bad situation by just doing a clean install onto one!

TVeblen said:

Because you can't get into Windows to start as the tutorial says I believe you would boot with your W7 disk and instead of selecting "Repair Computer" you would select the big Install Now button.

Having said that, I will still try that before I re-install. Thanks very much! :)