Sapo84 your suggestion made a good result but, I still want to add some more grain in the backgrounds, I think they weren't that bad in those upscales, using your filters is still better though. I read the filter descriptions before even though I didn't understand much, I'm kida newbie to Avisynth but I'm liking it a lot.
That script I made is from
this old post, I liked the result in that snapshot so I thought I could try using the same filters, I'm planning to upscale some DVDs for an hd tv because 480p didn't look really good on it.
Today I'm going to try warpsharp as foxy suggested, if it weren't for those ruined lines I think the upscale could be a lot nicer.