If your standalone dvd player can handle avi files, then all you have to do is burn them to the dual layer disk as data. Your player should show you a list of avi files on the disk and let you choose which one to play.
Normally you would want the avi files encoded with divx or xvid codec for best compatibility with those players that can handle avi files. And they cannot exceed resolution limits of the player…so no larger than 720x480 for an NTSC player or 720x576 for PAL.
So, does your player support divx avi files? Have you done this on single layer dvds already?
I cannot predict whether your standalone player will be able to play dual layer disks. Most can do this with no problems. Some are rather picky. Get the best quality dual layer disks and don’t burn them at top speed.
By the way, the only dual layer disks reliable enough for me to recommend are sold under the Verbatim brand. Burn them at 4x.