Yes, you can use all these on Shabbat if it is for a purpose which is allowed on Shabbat. For example, cracking nuts with a hammer, or using scissors to open a bag. If you were negligent and forgot to take the Challah out of the freezer, you can slice it with a saw and then warm the slices on the Blech. Beyond that, we discuss the laws of Muktzeh, or, as some people pronounce it - Muktzah.