I have no idea in what way Inkscape will act differently with Wimp disabled
It seems to make it run with more of a win3.x style, but I can live with that ...
I managed to get back decently sized text for cursor pos, zoom and ruler as well simply by upgrading the GTK files.
Since I only use the standard theme i Windows I cannot tell whether this too disables Wimp, but it "works for me" since the text size was what annoyed me. Might be worth a try?
(first install inkscape a new or at least redo the earlier suggested changes)
Install the latest GTK+ (2.8.7) from gimp-win: http://sourceforge.net/projects/gimp-win/ and copy its files on top of the Inkscape files. The files from the bin directory goes to your main inkscape directory, the gtk directories adds to the inkscape directories with the same names.
Something like: cp GTK/2.0/bin/* inkscape cp -r GTK/2.0/{etc,lib,share} inkscape