Re: error: no device found grub rescue
Ubuntu is not installed. Your hard disk (250 GB) has two NTFS partitions. They are your Windows installation. Whatever you did something went wrong. Boot the ubuntu Live CD/USB and "try ubuntu". When the desktop loads open a terminal and run
This will install lilo to the live ubuntu session. next in termainal run
sudo apt-get install lilo
This will put a generic windows bootloader on your MBR so you can boot windows again. Reboot without the ubuntu CD/USB. You should boot to windows, provided that whatever went wrong didn't mess up windows.
sudo lilo -M /dev/sda mbr
From Disk Management in windows shrink your C: partition to make unallocated space for Ubuntu. How much space to shrink depends on what you want to do. If you want just a basic install with ubuntu ( / ) and swap about 10-16 GB should be fine. If you want a shared data partition for ubuntu and windows to read/write to then add space accordingly. If you are adding a shared data partition then when ready to install boot the Ubuntu Live CD/USB to desktop again and use gparted to make an extended partition from the unallocated space. Then inside the extended partition create a swap partition equal to your RAM. Then create an ext 4 partition 10-14 GB for ubuntu. The rest make an NTFS partition for your data. Now install ubuntu. You will choose "Something else." Highlight the ext 4 partition for ubuntu and click "Change." Select " / " as mountpoint, make sure ext4 is selected as use as. Continue with the install. If you don't want a shared NTFS data partition just create " / " and swap as above and do the install.
Always have a working back up of your files before starting any partitioning/installation operations!!! As you have just witnessed sometimes things don't go as intended. Hopefully your windows installation is still bootable.
Multi-boot: Arch linux, Ubuntu 12.04, Windows 7 & Windows 8