Ubuntu server terminal?

Question

I installed ubuntu server on my windows 7 computer and can't reboot windows 7. I want know if I accidently formatted my hard drive or if I accidently replaced my OS. How do I download ubuntu from the ubuntu server terminal?

alejandro@JandroMunoz: ~$ df -h
Filesystem            Size Used Avail Use% Mounted on
/dev/mapper/JandroMunoz-root
                      680G  1.4G  644G  1% /
undev                 3.9G  4.0K  3.9G  1% /dev
tmpfs                 1.6G  400K  1.6G  1% /run
none                  5.0M     0  5.0M  0% /run/lock
none                  3.9G  4.0K  3.9G  1% /run/shm
/dev/sda1             228M   29M  188M 14% /boot
/home/alejandro/.Private
                      680G  1.4G  644G  1% /home/alejandro
alejandro@JandroMunoz: ~$ mount
/dev/mapper/JandroMunoz-root on / type ext4 (rw,errors=remount-ro)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
fusectl on /sys/fs/fuse/connections type fusectl (rw)
none on /sys/kernel/debug type debugfs (rw)
none on /sys/kernel/security type securityfs (rw)
udev on /dev type devtmpfs (rw,mode=0755)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620)
tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755)
none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880)
none on /run/shm type tmpfs (rw,nosuid,nodev)
/dev/sda1 on /boot type ext2 (rw)
/home/alejandro/.Private on /home/alejandro type ecryptfs (ecryptfs_check_dev_ruid,ecryptfs_cipher=aes,ecryptfs_key_bytes=16,ecryptfs_unlink_sigs,ecryptfs_sig=71839318eaf89afd,ecryptfs_fnek_sig=2aaae6
alejandro@JandroMunoz: ~$ sudo fdisk -l

[sudo] password for alejandro:

Disk /dev/sda: 750.2 GB,  750156374016 bytes
255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00025c60

  Device Boot     Start         End     Blocks    Id  System
/dev/sda1  *       2048      499711     248832    83  Linux
/dev/sda2        501758  1465147391  732322817     5  Extended
Partition 2 does not start on physical sector boundary.
/dev/sda5        501760  1465147391  732322816    8e  Linux LVM

Disk /dev/mapper/JanbroMunoz-root: 741.4 GB, 741360009216 bytes
255 heads, 63 sectors/track, 90131 cylinders, total 1447968768 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/JandroMunoz-swap_1 doesn't contain a valid partition table
alejandro@JandroMunoz: ~$ sudo parted -l

Model: ATA TOSHIBA MK7559GS (scs1)
Disk /dev/sda: 750GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos

Number   Start   End   Size   Type     File System  Flags
 1       1049kB  256MB 255MB  primary  ext2         boot
 2       257MB   750GB 750GB  extended
 5       257MB   750GB 750GB  logical               lvm

Error: /dev/mapper/JandroMunoz-swap_1: unrecognized disk label

Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/JandroMunoz-root: 741GB
Sector size (logical/physical): 512B/4096B
Partition Table: loop

Number   Start   End   Size   Type     File System  Flags
 1       0.00B   741GB 741GB  ext4

Answer 1

The text from the command line that you have included does not show anything that looks like a Windows partition, so it is highly likely that you have installed Ubuntu Server to the entire disk, destroying your Windows system. While it is extremely unlikely that you could recover your Windows system, it may be possible for you to recover some important documents that it contained. You can follow these instructions for doing so, starting with shutting down the system immediately (sudo shutdown -P now) if you have not done so already.

You'll need a live CD/DVD or live USB flash drive for this, but you should not attempt to create it on the current Ubuntu system, because (1) the longer you run the Ubuntu Server system, even if you are not doing much with it, the greater the risk of irreversible data loss from the contents of the old Windows partition, and (2) if you were to download a large file (like the Ubuntu desktop CD .iso image) on the system, that would be very likely to overwrite data that had belonged to files that were stored on the Windows system, very possibly including the important documents you wish to recover.

If those instructions don't enable you to recover your lost files, then you'll have to decide whether or not it's worth it to hire a data recovery specialist, which could cost thousands of dollars. You should probably not hire someone who is not a specialist for this purpose if these methods are not successful, because only a specialist is likely to be able to recover data not recoverable by those methods.

As for getting Windows back, you will need to reinstall it to achieve this. If your computer came with Windows but did not come with installation media (like a CD, DVD, or USB flash drive) then it is usually possible to order a Windows installation CD/DVD from your computer's manufacturer at relatively low cost (certainly much less than it would cost to buy another copy of Windows providing a new and separate license).