No he's not.
An anti-hero is essentially someone who is deeply flawed but the audience can still get behind and emphasize with, despite their faults.
Walt at this stage I'm finding it difficult to root for him at all, and I'm quite looking forward to seeing his downfall.
Although I guess the cold open in the first episode when he buys that machine gun suggests he might find some sort of redemption.
an audience can get behind a villain. you rooting for someone doesn't make them a hero or villain, their objectives dictate that.
here we have a man that created and sold drugs to provide for his family.
the argument to make him a villain is does he even care about his family anymore or is he just doing it now to satisfy his own ego? even then he could do a heel turned face spin in the end and what you consider villainy from him would have been an intermission in the arc of a character that started out good and finished that way.
very interesting character but to me calling him a villain insults real villains.