I have had a similar experience, but I can't get away with asking the user to view at different resolutions!
Why? Well, some of our customers use WebTV, yes WebTV!. You can't request them to change the screen resoloution!, and they have a smaller area available than VGA! (544 x 372 pixel).
So if you realy want to develop sites which 'Reach All', then do some testing with WebTV. You can get a WebTV emulator from developer.webtv.net.
This will then show you your design shortfalls, and where you need to address your design time for multi browser page delivery.
I use a mixture of client and server side script to find the browser and screen/browser resolution, then deliver the correct format. Some of this is handled with XSLT on the XML raw page data. This keeps the ASP work to a minimum.