Window Firewall not opening

Hi everybody,

I'm new here and my PC knowledge is somewhat limited, so bear with me.

My parents are running Vista Home 32 bit on a Dell Inspiron 530, with AVG 9.0 as the anitvirus. On trying to open Window Firewall, it comes up with the message "Due to an unidentified problem, Windows cannot display Windows Firewall settings". They have contacted AVG assuming its a conflict where 2 firewalls cannot run at the same time, who then direct them to disabling AVG's firewall - however for some reason the help emails direct them to a menu that isn't there (presumably AVG don't call a Firewall a Firewall, as I looked myself and couldn't see anything).

Unfortunately as they are my parents I'm sure this isn't half the information needed to solve the problem, but that's the best I could get! I did a quick search on Google and have seen that AVG 9.0 conflicts with Windows Defender - this is turned off, which AVG does automatically on install - but the majority of people with the above problem are on a network, whereas this is a home system.

Could anyone help please? Thanks.

Welcome
The suggested combination for Vista is Microsoft Security Essentials and the Windows Firewall. They are both made specifically for windows and work great together. In addition download and run a weekly scan with the free malwarebytes. You will not have anyproblems and they will be easy to operate
In addition your AntiVirus has been the cause of several BSODs (Blue Screen of Death). If you are not familiar with the term, lets just say you do not want to use any software that may include a condition which includes the term death in its name.
Bottom line, change the anti virus.
In addition Defender is part or Security Essentials and you will no longer need to run that software.