Windows can't complete updates undoing changes

Hello Friends,

I am new to this forum and this is my first post, please help me regarding the windows update problem. Seriously friends i am completely feed up with with these update problems. Previously i had windows 8 installed in my pc along with Ubuntu 12 (now i updated it to 12.0.4). Few weeks i got windows 8.1 update and then problem started i got a message as follows
"Windows couldn't complete update undoing changes please don't turn off your computer".
I waited for many hours but still i was getting same message, also if i turn it off and on many times i got the same message.

Now 3 days back i read some other forums and in that it is mentioned that i should enter into safe mode and uninstall all the latest updates. So i uninstalled all the updates of last 2 months, i was able to login after doing that but my computer become very very very slow. I cant even open a folder for 10-15 mins. So please help me what updates i need to re-install again ?? If i go to control panel i can that a message that i need to install 40 updates but when i click install it keeps on going. Please find the updates to install file as attachment.