a good Question.

I think she was someone who did want to be embarassed by her son being laughed at. She wanted to save him and her from people laughing at him. I am so glad she did she wa a little hard on her son in forcing him into acting.

This is a really great question! This is the only time that I didn't respond right away, I took my time and talked it over with other folks before I responded. Most anyone I spoke to and I agree that when the short starts out she is clearly the villain or villainess that only last to the scene where they are still in the house with the ladies group. She still seems as a villain when she calls out " Spanky , Spanky Mother can't hear you." When they get to the theater she seems to fall under the influence of the Grandmother and the more important The M C. They seem to be the true villains od "Beginner's Luck ". Spanky's mother seems to be manipulated by the Granny and the MC and they cleverly maneuver her into the position where she becomes so vunerable . By the time Spanky takes the stage they pretty much have her where they want her.

So I'd have to say she starts out as the villain but quickly becomes the victim.

Regarding the vixen part ,Spanky's mother does have some very strangely sexy poses. The way she sits on the couch arm or the chair arm with her legs crossed. The way she bends down in front of the gang some say that's sexy. The way her neckline is low on that dress . The way she gets down on the stage floor with the pole looks really sexy. the way she moves when she is trying to get her dress uncaught. So for sure she is a vixen or maybe a super vixen.

Spanky’s mother is not a villainess nor anywhere near a snob as today’s mothers are portrayed in these un-reality shows. Her character is just bad enough so that you do not turn her off with discuss not is she good enough that you will feel sorry for her. She is a balance of a woman who is blinded to the fact that her son wants no part of the stage, she is in fact a stage mother whose life and self-worth revolves around and depends upon her son being on the stage fulfilling her dream of him.
So she is a strong willed woman who will not be stopped even by a man as evidenced by her refusal to give up after the MC grabs her and hauls her back by her arm and tells her that she cannot break up that act. Yes she is more worried that that the laughter of son looks bad on her. So she is not so much a villainess, she is more an aggressor. She does become the victim but not of cruelty or vengeance but simply a victim of a comedy of errors.
Due to her not listening to her son or mother about his unwillingness to act; and that she is actually blind as to what her friends think that she misses their reactions to him and their sarcasm as to his winning first prize she sets Spanky and the gang to plan a way out for him. The first error.
The second was when Spanky had changed his mind about losing and helping the girl. Like most kids he probably thought that everyone there was not happy about it until he talked to Daisy.
The third was when he told his mother the message to give the gang. “Tell them I don’t want to lose now, I want to win!” Blind to the words he spoke she was ecstatic that she heard him say that he wanted to win saying, “But of course!” Then Spanking asking her, “Now what are you going to say to them?” Her reply “I’m going to tell them that you got to win!” Spanky happy with that agrees.
The fourth error was telling the gang “Listen boys, we want Spanky to win. Do you understand? Remember he’s depending on you.” They half hartley agree but are confused.
The fifth error was Spanky checking to see if they got the message and the gang mistakenly taking his gesture as everything going to plan. So they ignore what his mother said to them.
Then the sixth error at the theater her confrontations with the MC sets his attitude up for Spanky’s rendition and the audience’s reaction to him and to her. He will not let it stop especially since it is upsetting her and her idea of her son’s acting ability. This also can be seen by her mother’s laughing and unspoken agreement with the MC.
The seventh error was her mother laughing at the whole thing and seeing her daughter’s grand scheme for her son crashing down around her sees a chance to further her daughter’s embracement by raising the curtain and making her part of the act. She had nothing more in her mind than that. From the angle her mother was on she did not see that her daughter was already in the audience’s view.
The eighth error was Spanky’s mother sliding between the curtain’s while she was putting all of her might into pulling Spanky to her because Spanky was holding on to the edge of the stage. Pulling herself halfway out but with the curtain still in contact with her so that when her mother pulls up the curtain the scrim hooks (whose purpose is to come together so the curtain rises evenly as one piece and not flapping) comes together under the rear hem of her dress securely hooking it with no way to unhook it while the curtain is moving.
So all these little errors come together to dis-dress her. Her mother joins the audience’s roaring laughter at this coming together of theses comedy of errors. She is a victim but of circumstance not a planed attack.