How can I change 5 lines to a polyline...???

You can use below lisp,

(defun c:pp () (command "pedit" "m" (ssget) "" "y" "j" "" "") (princ))

so you can use pp command...

Anyone know about creating a single polyline (or 3D Polyline) from a polyline, an arc, and a helix?  I have a drawing that I am creating a video showing multiple angles of it.  I have drawn the path that I want to use for the camera, though I used the three previously described objects.  In 3ds Max there is a "Weld Vetices" funtion that I can't seem to simulate in AutoCAD 2009.  If you try the pedit funtion and join, it will prompt you that they're non coplanar objects.  If you try to fillet or trim the polylines, nothing happens.

Thank you for the lisp; it does have some cool uses, though it's not helping with that situation.  First the helix is not qualified as a polyline, so it won't allow me to select it.  Second when trying to join the arc and polyline I get the error "1 object (s) were not parallel to the current ucs".  Basically I have these objects drawn in two different planes, though I have joined the end vertices with the snap and move command, though I need to join then to a single polyline to use it as a path for a camera.  I have some others ways that I can do this (mainly redrawing the whole path with a 3Dpolyline and being really careful and accurate).  So now it's just for my knowledge to hopefully quicken my ability to draw later on... everyone is constantly learning new ways to do things.