Automated modification in registry due to virus

My computer became infected with virus as I used a USB drive containing virus.
Now I was unable to to set 'Hidden files and folder options' to 'Show hidden files and folders' or other changes to 'View' under 'Folder options'.

The default IE home page is automatically changed to symantec page.

Also I was unable to edit registry at all. To make the registry editable download the file named 'unhookExec.inf' from http://www.symantec.com/security_response/writeup.jsp?docid=2004-050614-0532-99. Save the on your hard disk, right click and select install. Reboot the computer.
In order to set 'hidden files and folder' under My Computer> Tools> Folder options> View; you need to make changes to the registry.
HKML\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\SHOWALL
In the right hand side pane check for 'CheckedValue' and set the value data to 1 instead of 0.
For changing IE page back to your default look for entries in registry as shown below and change it to default.
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\"Start Page"
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main\"Window Title"