A couple of points
- those boards will both do fine for a simple workstation.
- the reason they are cheap is they are being phased out
- the world is moving to SATA (vs IDE, also now called PATA)
- neither board supports DVI (for flat panel displays). VGA will be ok but it will limit your visual quality and what size display you can use. I LOVE my 1680x1050 widescreen monitor. having more display area has become a necessity to me now. it makes PCB design (among other things) sooo much easier.
- neither board can support dual monitors
- the NVidia 6100 is pretty old at this point and the drivers may not easily support larger resolutions (especially widescreen), depending on your OS. If you have an LCD display, you will definitely want to use native resolution.
- If forced to choose between the 2, I'd take the one with PCI express as that's the way expansion cards are going.
- Load it up with memory - at least 2 GB. That's the best way to get good performance.
On the monitor issue - flat panel displays have really fallen in price - 22" widescreens are now < $300. Don't scrimp on your eyes...
My cost effective workstation board would have 4-6 SATAs, PCI-e 16X and 1X, external dual DVI out video card, a couple of PCI legacy slots and room for 4 sticks of ddr2 ram. This will cost you a bit more but gives a lot more room for growth. I'd guess around 225 for that (including the video card).