Help!! Blank Screen

Hi there, anyone out there with any idea of what has happened.

As a newbie thought i would try the LOCK option, one of four when you double click on the exit button bottom right.
Fine it "closes" down, then when you press any button as if you want to use it again there is a small box where it requests a password. I entered the root password and yes it all opens up again.
Fine, but experimenting that this would be a useful security option in the future, after the next time of engaging LOCK I then turned the machine off by the power button. Waited a minute and then turned it on again by the power button, expecting the little box again asking me for the password- but no............
The machine goes through the Acer logo. F2 and F12 option screen shot, then the Blue user type screen appears to be opening but then it all goes black, no button seems to bring it to life, or allow you to enter anything.
Tried it a few times and the same thing happens.
Any thoughts appreciated on how to restore it.

 

Since posting this searched the forum for possible solutions. The F6 button that effectively turns on and off the power to the screen was cosidered. Then there seemed to be similar cases where others had used the Macles emergency recovery solution.
Newbie- so only had a vague notion of making the stick FAT, then dont fully understand this flashing the bios- what does that mean?
So....in the end went for the acer recovery disk method. Trepidation with this as posts of it not working. Have a external optical drive so dont have to go down the making the usb stick method (numerous posts of horrror stories read on this).
Well despite the acer instructions not that comprehensive have now restored it , it works like out of the box etc.
So....... I guess doing the sequence i reported creates that outcome- strange but i guess when the build these machines etal they cant work through all the possible consequences and design out all the flaws. MS may have issues but they do seem to work through this and provide failsafes. Is there the equivalent of System restore points on the AA1?
So I am learning, it was early days with the AA1 and no important data on the machine as i was anticipating issues.
IMO- any newbie DOnT USE THE LOCK FUNCTION

Back to finding a workable way of data securing it. Next step to play with the Boot password idea. Still dont know what the Change password option in settings does- Which ..@.!.. password will it change?

Any newbie wary of the USB recovery procedure found this video of how to do it-http://www.theacerguy.com/2008/09/aspire-one-recovery/