Norton Internet Security 2009 has caused me problems.

I run a pc under Vista home premium and have had NIS 2008 installed. I tok up the option to install NIS 2009 and my computer crashed part way through the installation. I can now only run in safe mode (with networking). When I try to boot normally I get a blue screen with  a message referring to SYMEFA.SYS and a PAGE_FAULT_IN_NONPAGED_AREA.

I tried contacting Norton but the website won't let me email - it wants to chat but you can't chat in safe mode.

 

How can I get running again?