If I understand this correctly, you are talking about fairly standard A/B Roll editing. If this is the case you will need editing software that supports A/B Roll and usually multiple video layers. Typical examples are Adobe Premiere, Ulead Mediastudio, AVID etc etc). For more info on these products check out Marc Peters post at
http://www.videoeditingforums.co.uk/viewtopic.php?t=548
Therefter place camera 1 on Track A and Camera 2 on Track B and simply make the cuts where you want to move between one camera and another. Remember to synch your cameras at shoot time though.
Good luck