Hi,
1. Are you able to boot to the desktop?
2. Does this issue occur with Internet explorer?
First you need to try safe mode and check if you are able to boot to the desktop.
Follow this below provided link to start your computer in safemode.
http://windows.microsoft.com/en-US/windows7/Advanced-startup-options-including-safe-mode
You may also try checking for the last known good configuration in the advanced boot options.
I also recommend you to update the display drivers and see if it makes any difference. You must be logged on as an administrator to perform these steps.
a. Open Device Manager by clicking the Start button, clicking Control Panel, clicking System and Maintenance,and then clicking Device Manager. If you are prompted for an administrator password or confirmation, type the assword or provide confirmation.
b. In Device Manager, locate the Device, and then double-click the device name.
c. Click the Driver tab, and then click Update Driver and follow the instructions.
Try to follow the below provided link to Update a driver for hardware that isn't working properly and check for the issue.
Update a driver for hardware that isnt working properly
http://windows.microsoft.com/en-us/windows7/Update-a-driver-for-hardware-that-isnt-working-properly
After updating the display drivers reboot your computer and check if the issue gets fixed.
Thanks and Regards:I. Suuresh Kumar - Microsoft Support. Visit our Microsoft Answers Feedback Forum and let us know what you think.