I neglected to quantify the “this’ ,which is eiter allowed or prohibited by the various Poskim. the remo says the following” “likones lebais hamedrash oh lehispallel oh lehazkir es hashemoh ligah besefer torah”. translation: ” women should not go the the shul, or pray or mention the name of hashem or touch the sefer torah”
This is a very comprehensive prohibition. It is clear from many minhagim and today’s practice that there is NO widespread minhag to prohibit women from entering the shul or praying while they are “niddos” or saying Hashem’s name. if you accept that women can do this and are not subject to minhagim that prohibit this, there is also absolutely no reason to isolate the touching of a sefer torah and prohibit this while allowing the other practices, as it is pretty clear they issue from the same ruling.
anyway- the actual halcha is clear (joreh deah 282)- there is no prohibition for women to refrain from touching a sefer torah during the days fo “niddah”.
as far as dancing on simchas torah- allow the minhagin to develop for different groups.