Well sounds to me like you know what the metering modes do its just a case of using that knowledge to either set the exposure compensation to allow for the over exposure or to go into manual mode and set your own exposure. In the light bulb example i you set your exposure off the bulb everything as you say would be over exposed so you would set your exposure compensation to -2 to adjust for that.
Heres a link that explains perfect exposure but im affraid it goes through about 7 video clips between 10-30 mins long lol but if your up to it, it may give you an understanding:
Photography Tutorials on Vimeo
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You cant fool all of the people all of the time, some of the time all of the people will some of time but not all of the time as some of the time all of the people will some of the time but all of the people will not all of the time
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