Setting the center point should not be any different when using dynamic data. What have you tried? There is a map.setCenter(point, 13); in the php file that you should be able to use to set the center. If you update this code to be like this:
map.setCenter(new GLatLng(30, -98), 13);
You can specify coordinate values as the center point.
For the problem you are experiencing with the map not initializing to the region with your points how often does this happen for you, and are there any steps that you can take that will reproduce this result every time?
To stop the info window from displaying you will need to find some code in your maps php file that looks like this:
map.addOverlay(marker_0_<?php echo $Recordset1_id; ?>);
/*marker_0_<?php echo $Recordset1_id; ?>.openInfoWindowHtml(address_0_<?php echo $Recordset1_id; ?>.infowindowtext);*/
If you comment out the second line like in this example you will prevent the info window from displaying. It is important that you only do this to marker_0_ line that occurs after the map.addOverlay line. There are other spots in the code where this second line will appear and you can't comment out the lines there or the map will not display.