You will not reduce the size of the screen display until you increase the resolution. Since all the ''soft'' fixes have failed (except that you apparently have not yet tried new drivers), you should consider the possibility of a hardware problem. I have had shaky screens when the monitor was going bad and when a cable connector was not making good contact; I would imagine a failing video card could also cause such symptoms.
The first thing I would do is shut down and then unplug and replug the monitor cable three or four times; this should wear off any oxidation on the pins/contacts and improve the connections.
If the problem continues, could you borrow a friend?s monitor for a trial? If another monitor works OK, then yours needs repair ? but today the repair might cost about as much as a new monitor. If the problem remains on the substitute monitor, the video card or its driver should be suspected. Did you not get a CD with your system containing copies of all necessary drivers? You could reload the video driver from there. If you do not have such a disk, you must get the video driver from the Web.
You never told the manufacturer of your system; however, both the IDE and video controllers are VIA, which are used on several lesser-known motherboards. Strange, but I could find nothing regarding the VT8306/VT8601 chips on the VIA site; however I did find the drivers available for those chips on some motherboard sites: for Msi mobos, for ECS mobos, and for Biostar mobos. Belarc should have told you the name of your mobo, but you did not pass it on. Take a look at that and go to that site for the driver.
Another site, Driverfiles.net also has the drivers, but not tied to any specific mobo. You could try it if you can't find the mobo site.
If you reload the driver and the problem persists, it probably is a hardware problem with the video chips, which are most likely integrated on the mobo. You then really have a problem as that cannot be easily repaired.
BTW, in one post you said you got an e-mail saying the issue was closed, but I did not notice anything about this in an earlier post. Who sent the message, and what triggered it?
Hope this helps