what makes a better video? having something recorded at 30fps vs 15fps OR having something recored at 800x600 vs 640x480
I--and this is just my opinion--don't think 15fps is good enough. It will "skip" when shown on tv/computer (depends on the video though). I think you should go for something greater than 24fps (which is what motion picture uses, if I remember correctly). So *I* would not consider 15fps to be decent video...
As far as resolution is concerned, standard television in North America (NTSC) uses something like 720xSOMETHING. Camcorders and DV shoot at this tv resolution (although they also can shoot at higher HDTV resolution if I understand it correctly). If you have 640x480 resolution, it is below tv resolution. Obviously 800x600 is above standard tv resolution (still not HDTV quality though) but hte problem is that practically no digicam allows 800x600. I'm not an expert but I only know of the Konica Minolta Z2, AND the funny thing is that the Z3 (the latest version) only has 640x480 so I'm not really sure how good 800x600 was on KM Z2 (why would the manufacturer pull the higher res?). (I don't know anything about A200 and if that has 800x600@30fps, that's cool). So to sum up, 640x480 is close to tv resolution.
If you are only going to be viewing video on the computer, then the resolution isn't THAT important (although it still matters). If you play a smaller resolution on the computer, it will show up in a smaller window but the sharpness/quality will look just the same; if you play a higher res, it will play in a bigger window.
Of course, others may have their opinion on what is acceptable resolution and frame rate...
does anyone have a link to a video of the same thing one recorded in both ways so I can compare?
I think Steve has some videos at the end of his reviews (in the sample pictures section). So check out a couple of reviews. DCresource.com, another camera review site, also generally has a video in their review (as well as in their sample pic section). Look to see if they have samples for Konica Minolta Z2 (I'm not sure if anyone reviewed that).