A. This has always been a problem with the SQL tools - it may be bugs in the SQL tools code, but then the same exe's/dll's work fine on NT. The most likely reason is the sheer amount of gdi/icon/graphics type resources that they use is exposing some sort of Win9x limitation/bug.
You should try resetting mouse settings/pointers back to defaults, and also, if you're using an Intellimouse, then loading the very latest drivers.
You could also try applying the latest service pack/edition to Win9x, but the best bet is to develop with NT clients.