"media player and my search doesn't works as well."

Have you ever used a registry cleaner or altered what Services that run?

If so, that can be the cause. The search might be fixed with this article -> http://www.dougknox.com/xp/scripts_desc/xp_fix_search_error.htm But you didn't describe your search problem well enough so I can't tell if this is your fix.

As to WMP, I don't use it, but the errors are plentiful. You'll have to tell more.

About auto update. There are a handful of services that must work. Most of the time I see this an issue if the owner read a Black Viper web page. Tell more.