i'm not certain i know what yer asking but i'll give it a try.
to get a close up you touch the screen at Btm on my fascinate and there appears a small slot containing a + or - sign.. then just touch the PLus and you can zoom in.. as for the google map being a screen saver,, welp i would be leary of that anyway.. open the map alone and you might find better choices.. open latitude also and then enter yer address if yer at home and let it use GPS to find your house,"""Do Not Use Verizons Location Services" use "Standalone GPS service and Google Location Service" located in the settings on your phones "Location & Security" settings
hope this helps as i said yer statement left a lot of unknows. have a good day..