Yes, you can combine multiple video tapes onto a single DVD. Because a DVD can only hold so much data you are limited in the amount of video that you can put on a DVD; about 3 hours of video can fit onto a DVD.
StashSpace makes it easy to transfer multiple tapes onto a single DVD. After having your tapes transferred to digital use the free StashBox video editor to combine video tapes onto one movie. You can put up to 56 video scenes and 3 hours of video onto a single DVD.
To transfer more than one tape to DVD go to the video transfer order page. Send in your videotapes to be transferred to digital, and then go online to combine video tapes onto one DVD.