Best way to go about removing heavy dot crawl and rainbowing?

[DominoDeer]

Hello, I recently found out about AviSynth and how great it is for restoring DVD content. I've been working on a project that requires me to clean up some SpongeBob episodes from official DVDs, and some episodes I have are in really rough shape.

I have a couple episodes ripped directly from DVDs that are full of heavy rainbowing, dot crawl, and also haloing in some cases. I'm very new to using AviSynth and I would like some pointers on if these are too far gone to save, or if I could potentially clean them up, and what tools would be the best for the examples below. Thanks!

https://imgur.com/a/MJ7kMeG

[Mounir]

One of the best i've found is this one:
#for a source with heavy dot crawl
MPEG2Source("MyVideo).d2v", cpu=0, info=3)
main=last
main
bicubicresize(480,320)# NTSC source
spline64resize(720,480) # NTSC source
lsfmod
filtered=last
main
mt_edge(mode="prewitt",chroma="copy").mt_expand # use the mode prewitt (more agressive for heavy dot crawl)
mymask=last
mt_merge(main, filtered, mymask)

for normal dot crawl

BilinearResize(width/2, height)
Sharpen(0.3,0.0) # adjust to your liking
Spline64Resize(width*2,height)