Subtitles on DVDs are stored seperately in the .ifo files. They are actually just pictures with timing info so you can't just "rip a movie with the subs" because the subs are seperate things. To apply them to your ripped video you have to use a plugin called VobSub which will use the .ifo subtitles and place them over your video. You can do this either in virtualdub or avisynth.
In any case, there is a full subtitle guide on doom9 which does answer everything.