I'm a Windows user and I have no experience with Linux and Ubuntu.

I installed Ubuntu 12.04 on my netbook (Asus 1215B) and everything works fine. Yesterday I ran the "update application" and updated over 120 "things" (I have no idea what exactly). After that I was asked to reboot, and I did.

Ubuntu starts again and at the load screen with these 5 dots that normally begin to change color, it freezes. After 20 minutes I took out the battery to try another reboot (yes, not the the best idea), and now nothing happens. 

I boot from the HDD and I get an Error

> 
> BOOTMGR is missing.
> 
> 
> 

I have important data on the hard drive. Is there an option to get this fixed? Or if not, to at least get the data from the hard drive?

Ubuntu 12.04 64-bit

Edit: it is ONLY Ubuntu on this Netbook, which uses the whole 500gb HDD as 1 Partition.
Filesystem is NTFS.
Whole Hardware seems okay.
The USB drive which i used to instl the Os was formated in fat32