Windows 7 - Black Desktop Startup w/ Libraries Window

Toshiba Satellite L505-S5988
Windows 7

Every time I start up the laptop the desktop is black, there is no icons, and there is no bar at the bottom of the screen, and also the Libraries Window show up at the start up.

Dose anyone know what this is, and how I can fix it?

Thank you very much in advance.

This laptop also did not come with any CD so I don't have an option to reformat do I?
I think it maybe a virus but I'm not sure and I don't know what to do about it, when I try to open Mozzila Firefox from that Libraries Window i get a msg saying:

Microsoft Secuity Essential Alert (another window)
Detected items: Unknown Win 32/Trojan
Alert Level: Severe
Reccomendation: Remove
Status: Suspended

I click apply and it says Unable to remove threat then it want me to scan online...
but i havnt tried pressing that button...

I've also scan with avg but even after it didn't fix anything.

please help Thankyou again for anyhelp i may get and +rep

Yes you have a problem. Repost in the security forum and you will be helped by experts. To get you started, they would want a MB log. download this and run the full scan after you update.
Malwarebytes' Anti-Malware: Malwarebytes

If you are unable to get into Windows 7 to run AV, burn to CD and run one of the bootable AV's here: FREE Bootable AntiVirus Rescue CDs Download List

If Windows 7 will still not start, burn a Windows 7 Repair CD, boot into it to run Startup Repair repeatedly. If this fails, try to System Restore before the infection.
System Repair Disc - Create
System Recovery Options

If this fails, copy out your files using Repair CD with this method: Copy & Paste - in Windows Recovery Console

You can then run Factory Recovery which is triggered on Toshiba by either holding down the 0 key at bootup, or tapping F8 key repeatedly, choosing Repair My Computer and then Factory Recovery from list. Otherwise look for Recovery key(s) given on first boot screen, or in your Manual at Support Downloads webpage.