R1 is never 25fps, all regions within R1 are NTSC, if you see otherwise methinks they've screwed up... or at least this is to the best of my knowledge.
PURE NTSC is 29.97fps. This is becoming rarer nowadays, it is only home video cameras and older television cameras that shoot at this framerate. New TV series are shot at 24fps.
NTSC DVDs are often artificially '29.97fps'. This is actually a falsehood, these are only 23fps, and is done to make playback on NTSC machines 'better'. Its pretty much dedundant nowadays, like Interlacing is, but it remains in place due to conservativism in the industry.
NTSC, R1, are never any other framerate, they are either 29fps, or 23fps.
PAL as a format came out after NTSC and is superior in everyway, except for one debateable factor. These are larger resolution, more accurate colours, etc. The only thing NTSC holds over PAL as a format is that NTSC more accurately matches cinema fps, that being 24fps, where as PAL is a single frame out.
With this info in mind, you should always ensure the following:
a) No rip should ever be 29fps unless it is pure DV/TV at this natural frame rate
b) Always try FORCEFILM (covered in the gknot guides you should have read by the way
) first when ripping the vobs to get the framerate correct for NTSC, failing this, use ITVC in gknot. You should always do this on R1/NTSC DVDs where the framerate is artificially 29fps.
bi)If you do encode a movie at 29fps, when it should be 23fps, then you have 6 extra frames per second of repeating data, meaning you have a lot of your bitrate wasted every second, meaning you have a significant wastage of video data, meaning your movie looks worse than it should. Add into the mix that these repeating frames make the video stutter (your seeing the same frame 6 times in some cases).
c) NEVER change between picture formats, ie. PAL -> NTSC, NTSC -> PAL, there's a huge degregation in quality and its really, really not worth it. The only circumstance is when you have a truely dreadful setup that is a nazi about the picture format it takes.
d) NEVER encode at a framerate that doesn't match the format. Most programs will prevent this of course, but its worth stating.
People may think a couple of frames don't make a difference. Times 6 * 60 * length of movie, lets say an hour and a half....
6*60*90 = 32400 wasted frames.
The extra frame in PAL vs cinema also accounts for the difference in runtime you see between the home video and cinema releases
hopefully should see results of my labours soon 
already knew pros n cons ov diff versions etc jus wasnt sure whether i had to change the fps from 29 to 25 or whatever cos never done a r1 (ntsc) b4 