your monitor does not plug into a Serial port. a VGA/SVGA port connection looks similar to serial, but they are not the same.
the USB hub is a good idea - espcially if you can find an external (as in you plug it in and don't have to open your computer case) one at a good price. you may also be able to purchase an internal I/O (input/output) card. they normall include both a serial and a parallel (old fashioned printer) connections. i don't know if they're available as external or only as internal. if you go internal they are super easy to install.
check with the dealer who sold you the computer.
those whose printers don't communicate with Windows 7 should check the drivers/support pages at the printer manufacturer's website. you may find updated drivers and other software to download for free.