So this is my first time posting, bare with me if my formatting is atrocious. x')

I've been using Linux for years since while it isn't always convenient, it's one way my dad made sure his teenage daughter never got her computer loaded with viruses with all the things she downloads haha
Though, I don't have much knowledge about anything linux. My problem is that since he passed away, all of the computers in the house are locked. Even my own laptop. I can access my account but I can't download any software, update my ubuntu or anything for that matter, etc.

Is there any way to completely reset my computer? I'm okay with wiping absolutely everything, as long as I can start fresh.

Here is the info I know:
Dell Latitude 830
Xubuntu 14.04? (I'm not sure which version number I'm on..)
I can take screenshots of anything you need, just ask ^^
Thank you for any and all help!

I'm sorry for your loss

I'm taking a guess that the reason you cannot access them is to do with the root password?

Before you do anything as drastic as a full wipe try resetting the password with the instructions here
(he talks about typing 'passwd jorge' - to change root just type 'passwd'

If that doesn't work then yes a clean install might be the way to go, grab a copy of xubuntu here - or for 14.04 here

And then make a usb stick from it here or burn it to a DVD

Once you boot from that you should be in a live environment, you can proceed to install from there and the installer is pretty simple - while you are in there you can also save any files that you need to keep!

If you able to get to a terminal on the system, issue
and enter your known or usual password at that system.
Your password will hot be echoed on the display.

If successful you will have "sudo privs" (elevated) on that system.

Allowing this command to run is non-destructive to the system and only serves as a privilege test of the known or usual user
logged in when it is executed.

This is quite different than "the root account" or locked workstations.

Sorry for your Loss.

Following on from Habitual: you either do or do not have sudo access, depending on how your father set things up. If you can do updates with sudo, using your own password, then you can change the root password with sudo too. The command sudo su will give you a root shell. Then you can use the passwd command to reset the root password to something of your own choice.

If you can't use sudo, then the process is slightly more complicated. You will need to download and burn a Linux image onto a CD or copy it onto a pen drive. I use SystemRescue for this sort of thing. Quite apart from this problem, it's a useful tool to have lying around for emergencies of all kinds.

Boot from that and mount your hard drive, then edit the unknown root password out of the /etc/shadow file. Someone here will hold your hand and take you through the procedure step by step. Once the password is gone, you can boot normally, log on as root without using a password and set a new password for the future.

Thank you.

And I was prompeted with "olivia is not in the sudoers file. This incident will be reported"
He was a software engineer so I'm sure he knew his way around and locked it up as secure as he could I'm guessing x')

Thank you Hazel, looks like hand holding will be needed since the sudo is locked up. I've got a pen drive on hand! The linux image would be an .iso file right?

That's right. You should choose the correct iso image for your architecture. Most images come in both 32- and 64-bit versions. Although you can boot from a 32-bit disk even on a 64-bit machine, you'll find a compatible format more useful as a long-term rescue device.

To copy the image onto the pen drive, just plug it in, open a terminal and use the dmesg command to find out what your system calls the drive. Then use the dd command to copy the iso file onto it. For example:
Of course it might not be /dev/sdb in your case; the last few lines from dmesg will tell you what device name you need to use. Just make sure you copy the image onto the whole drive (/dev/sdb), not onto a partition (/dev/sdb1).

Keep that drive in a safe place and you'll always be able to boot and fix your machines.

Thank you Remma, I selected the 32 bit .iso of Xubutnu 14.04 and I have a Usb stick and a CD. I would rather pick which is quicker/easier haha x')
So I boot and the option will be there? Wow this sounds actually quite doable, thank you!

http://imgur.com/a/lzjZZ That's what I got back from the terminal, (currently using my mom's computer to test drive this). When it come's to code I'm pretty much blind, do you think it'd be easier to burn it onto a blank disk?

http://imgur.com/a/uegns Turns out I already have an installation disk for Xubuntu 15.04? Would this work? :0

edit: http://imgur.com/a/SNdJp found 2 more disks both for 14.04

Oops! I forgot your main system is Ubuntu. If so, it's not the root password you need to get rid of, it's your father's password. But booting from another image is done the same way in either case. And you can certainly use your installation disk. Practically all modern installation disks act as rescue disks too.

Once you have another Linux system booted, you'll be root in that system. You just need to mount your hard drive (/dev/sda) somewhere convenient (for example on /mnt). Then find out your father's preferred username by listing the /mnt/etc/passwd and use the passwd command to change his password.

For example:
In the long term, you'll need to give yourself full sudo rights but you can do that once you are able to log on as him.

Thank you so much for you help Hazel, you're a life saver! Alright, this is my second time trying to catch the boot, when the system starts up it whizzes by so quickly x') I'll edit each time I get a step closer!
Edit: it's looking good so far, I'm guessing I have to sit back and wait http://imgur.com/a/yRnbP
^^

So, that's ok. It's doing it's job there. Reporting failures.
If you have an idea of the password and you'd like to try one or two or twenty, issue
Same on the password not showing, however, this is not a 3 step process as before, but
It is one step.
and upon failure, you'll see
and I still advise you write down attempted passwords.

Failing that, The link remma12 gave you or there are others.
Basically boot the system with a liveCD and edit the root account password to one you know
and reboot.

We can help.

Below is a way to gain control of your computer using a 'live' distro, as the root operator.

(Then you will need to set a new password for the root user account.)

You have a choice of methods. Either you can edit the shadow file by hand as suggested by fatmac or you can use the passwd command (the normal way to change a password) with the -R option to indicate the location of the relevant shadow file. The default shadow file will be the one on the CD that you booted from, but you will want to make the change in the one on your mounted hard drive. Use whichever method seems easier for you to understand. The most important thing when fixing a problem in Linux is to understand exactly what you're doing and why you're doing it. That's how you learn things.

In either case the first steps are to boot from the CD and then mount the hard drive on it. And as Ubuntu distros don't encourage root logins, you might prefer to change your father's password rather than the root one. He after all was the one with the administrative rights.