If you can't change the port, then it is an automatic device expecting that you have a newer computer and will lock out the IRQ thru the BIOS (modern because jumpers have been eliminated, so everything is done thru BIOS settings) . Somewhere in the BIOS you should find the screen dealing with IRQ. Those menu options you posted take you to more detailed screens where you should find the settings. Most likely, in order

Integrated peripherals
Advanced BIOS features
Advanced chipset features


Possible but not probable

Power Management Setup

Did you perform the DOS command line test dir >lpt1 ? This should be done first before you muck around with the BIOS. Epson is telling you LPT1 / IRQ 7 because that is the default setting for the card. That is the IRQ you should 'assign to legacy device' in your BIOS.

If your BIOS screen gives you the model number of the motherboard, post it and I can help you more.