If you are tired of her crappy behavior then don't allow it anymore. It is SO simple. You cannot control her but if you set boundaries her crap behavior will not be a part of YOUR life anymore.
At the very last, after this latest disaster you should be telling her: W: This will NOT happen again. I will no longer alter plans to accommodate you or your family on my weekends with the children. If a special day (b-day or whatever) happens to fall on my time I will make plans as I so choose.
In a matter of 24 hours your wife has:
*Changed plans on YOUR night with the children and as per usual, pitched a hissy fit when she got the slightest indication that she was not in charge.
*Shows up at your house when it is convenient for HER and has so little respect for you that she just bangs on the door and assumes you will be there (alone) and you will again accommodate her.
*She enters in YOUR bedroom (personal space) and chatters away while you are in a TOWEL. Attempts to extract information from you about your employment (don't think there isn't a reason she is doing this) and you TELL her everything she wants to know.
*Leaves you with the grunt work of getting the kids showered then basically tells you to bring them back to HER house because you are too stupid to dress your OWN CHILDREN properly.
*She ruffles through papers on your table that don't belong to her and without having to do any digging, you spill all the details despite the fact she should not be TOUCHING anything in your home.
Oh, and part of the reason she acted nice and interested about your job was simply to throw you a bone so you would do what she wanted about the van.
Wow, she sounds like quite a prize. If you are so tired of her and the sh*t she pulls then STOP LETTING HER.
Isn't this the same woman that won't even allow you in HER house unless she has approved it? Fine, that is her boundary. Yet you are okay with her barging in unannounced to boss you around, invade your personal space, look at YOUR stuff without permission and leave you with the grunt work in regard to the children. All on YOUR day with them?