I do microcontroller programming and my programmer uses the parallel port. Problem is, so does my printer! So, I bought a Lava PCI parallel port card and added a second port. It works perfectly and although I don't use it for mach (different computer) I cannot imagine any problems the card would create. The only hard part is finding the port address for software that wants the address instead of the LPT number but that's actually easy - just open up control panel->Hardware->Device Manager then look at the properties for the card. Under "resources" the address range will be listed, just use the first hex number. Mine shows 8C00-8C07 so I use 8C00.
edit: Actually, you have a Dell.. Dell like to do things in a non-standard way (or at least, they have in the past). Best to call them and ask if a PCI parallel port card will actually function in the computer and, if so, which brands are known to work. For instance, my buddy bought a dell 4-5 years ago and after a while his kids had Win 98 all messed up. He bought win 98 from the local store (del charged extra for the actual DISK for windows so he didn't have theirs) and tried unsuccessfully to install. It took a call to Dell support for him to find out the debug commands required to allow a non-Dell Windows to be installed (I was competely floored by this as I've been into computers since '79 and had never heard of such a thing). So, make that call - it may just not be possible to have a parallel port (though I'd be floored a second time if that were true).