Hard to say as I would be doing it all on the mac, I'm not really an avisynth guru, I tend to work out how to do something on *Nix or OSX and then pass the conceptual procedure onto people who know the PC free stuff to achieve the same results.
There is an entire forum over at doom9 though with plenty of arguments over the best ways to do it, it is well worth a read and you could pick some methods and use a rewritable DVD and make a few sample til you get the best result for your particular telly.
I can't recommend what level of filtering to partake in until I get my hands on a GOUT set.