okok I will tell you how to get this shit for sure working.
(on your home computer)
Download UBCD http://www.ultimatebootcd.com/download.html
-click one of those hard drive looking imjages with the red arrow pointing to it
under mirror sites
-the downloaded file is called a .iso file
-if under windows 7, right click the downloaded file> goto open with> click
windows disc image burner, pop a empty cd/dvd in a hit burn
-if under xp or vista, download the free tool poweriso http://www.poweriso.com/download.htm then follow their instrustions for burning a .iso file(will just be tools>burn in the poweriso app)
So now you have a handy cd/dvd you can plop into any computer and delete the admin password of. Let's use it.
(at work computer)
At the end of the work day tommorow, put the disc in and shutdown the computer. Now turn it back on. You should see a little prompt pop up that says press any key to boot from cd/dvd. spam your keyboard during this until something happens. If it doesnt go into the disc and start booting windows, try again. If that doesn't work, youll need to change boot order in the BIOS.
If you got into the disc, skip this step.
when you turn on your pc, youll see some image or text pop and and somewhere on screen it will say press <thiskey> to enter bios. Usually it's f1 or del. spam that key. In it is a simple list of settings you can change, just make sure cd/dvd boot is first, hard drive is second.
After you boot into the disc, goto HDD tools then Offline NT Password & Registry Editor. follow on screen instructions to delete the password for the administrator account. After that, boot into windows and log in using the username administrator.Pressing ctrl+alt+delete might help to get to a classic logon screen
Now your at the good part, logged in as local admin to the machine where theres no restrictions. press windows key+r (or just get to the prompt)(or just type it in the search bar in vista and win7) then type in dxdiag. This brings up a window with simple graphics info on it. Go to the display tab and look under name. Now go to the right driver download site for the graphics card maker. It'll either be AMD/ATI - http://support.amd.com/us/gpudownload/Pages/index.aspx ,nvidia - http://www.nvidia.com/Download/index.aspx?lang=en-us or intel http://downloadcenter.intel.com/default.aspx. Fill in the form with the appropriate info - just the name really found under dxdiag. Also now would be a good time to update java http://java.com/en/download/index.jsp.
install those drivers and your good. logg out and shutdown, If you can play minecraft the day after your good. This may look hard but it's pretty simple really. Don't let it be overwhelming just because it's alot of text/ looks hard. It's just simple steps combined