After Log-in My Cursor Disappears...

First, I would suggest you to follow these steps and run the Hardware and devices troubleshooter:

a. Press Windows key + W to search Settings.

b. Type “Troubleshoot” without quotes and click on Troubleshooting in the results displayed on the left side of the screen.

c. In the new window, click Hardware and Sound.

d. In the list of options, click on Hardware and Devices.

e. Click Next and follow the on-screen instructions.

Method 2:

I would suggest you to restart the computer in clean boot mode and check if it helps:

How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7 here: http://support.microsoft.com/kb/929135

Note: After troubleshooting, see the section “Reset the computer to start as usual” to return the computer to a Normal startup mode.