My PAL DVDs play on my computer. So yours should play as well. Also if you want a region free player that does PAL to NTSC conversion go with the Malata. I've seen it and it does damn good conversion.
You know, PC's don't "know" about a PAL/NTSC issue. It only becomes important if your graphic card has a TV-out - and then it depends upon what's supported by the GC.