Pyrex and Duralex are proprietary names of glass-based materials commonly used in kitchenware which are produced in such a manner which allows them to be heat-resistant. Although some are of the opinion that they have earthenware-like properties (see previous Halacha), Rabbi Ben Zion Abba Shaul (Or LeZion vol. 3, ch. 10) says that they have the same status as glass and simply need to be cleaned before Pesah.
Another area of concern in the kitchen are modern stove-tops which are made of a glass-ceramic material. According to the Institute of Science and Halacha (Israel), the crystallization method of this material gives it ceramic properties, namely hardness, yet it is still non-porous just like glass. Therefore, with regards to koshering for Pesah, they have the same status as glass. The part of the stove-top occupied by the elements are of least concern since they can be turned on and koshered through the process of Libun. Regarding the peripheral areas of the stove-top, Rabbi Levi Yitzchak Halperin of the Institute suggests that one pour boiling water on it three times from a primary heat source (such as an electric kettle). Alternatively, one can cover the stove-top with aluminum foil, excluding the actual elements.
Summary: Pyrex has the status of glass and only needs to be cleaned forPesah. The area of glass-ceramic stove-tops excluding the burners can be cleaned by pouring boiling water on it three times. Alternatively those areas can be covered with aluminum foil.