I am confused as to your definition of "subtitles". My definition is that a subtitle is the text that appears on the bottom of the screen when playing a (usually) commercial DVD - the subtitle text is the written form of the sounds (voice, music etc) occuring in the movie. You can turn "subtitles" on and off through a menu control on your DVD player.
In your submission, you seem to be refering to time/date that the video was shot as being a "subtitle"?
Given your reference to "finalized" DVDs I am assuming that your Sony HandyCam writes directly to a DVD. I believe that the video files on each disk will have the time/date information held in the file name.
Normally, when using a mini-DVD camera that writes to mini-DVD tape, if you capture the video to your computer in .avi format (your files will probably be mpeg2 or some possibly custom Sony format) then the time/date information is held in the file itself - VS has a preference bit that can be used to display this information in the preview window as you are previewing the clip. At no time does VS place this information into a viewable section on your rendered video output - you either have to do that manually by creating a title screen with the information (that you type in) or there are third-party programs that will embed it for you - but only if you have the video files in avi format.
Mpeg2 format doesn't retain the time/date of shooting, so cameras that record directly in this format "get around" this limitation by embedding the information into the file name somehow i.e. each time you stop shooting and start again, a new file is created on the storage medium that contains the time/date information.
So back to uour questions and assuming you are refering to date/time when using the terms "subtitles":
1. You can't "rip" the information from the DVD and have it automatically appear in the video somehow using any ULead product (or any other product that I am aware of).
2. As I mention above, the file names on your finalized DVD should have the information you require, so just look at them and then create your title screens (with the required information) in the shape and form you are happy with
Hope this helps,