(whithin comon sense)
there is a software that I like called Video Factory from Sonic Foundry it's about $69 and it has MPEG1 and MPEG2, AVI, WMV, QT and RM rendering.
second it depends in what format your video clips are in because some format's are closed formats like WMV. some formats are proprietary like QT and RM. some formats are open like MPEG1 and divx some formats are copywright like MPEG2 in which case you will need an MPEG2 editor like video factory.
Virtual Dub is fine but it's the poor mans video editor and won't edit MPEG2 and wont' render to QT and RM. If your looking for simple open stuff virtualdub will do. If your looking for more of an MPEG2 editor that can render video then Video Factory is more in line for that.