Internet Explorer Security Settings?

I have tried to search this but did not find what I needed.
I have done something to my Internet Explorer security settings so that now I can not get the Napster music (flash) player to work. Also I can not access some web sites. I think I have ‘Lost’ my flash player?
With Firefox and Napster I have the same problem.
After jacking around with all of the security settings I am sure I have incorrectly reset the settings.
Would someone please tell me how my security should be set so I will be secure and can use Napster?

What error/message do you see when trying to use Napster?

Well, I again jacked with all the settings. I enabled everything and now the Napster player works. So now I know I need to reset the settings correctly in order to be safe. Does anyone know what should be enabled or not?

. I’d start by clicking on the “Reset all zones to default level” button on the Security tab of the Internet Options control panel. I’m using WinXP Pro SP2, YMMV. If everything still works, I’d either leave it alone or try a few tweaks, depending on how comfortable I felt with the situation.
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. Error msgs would be a big help.