Dragonskin Boots have the fantastic ability of being totally immune to lava, meaning that it is possible to walk on it without taking any damage! This of course comes with the price of first obtaining dragon scales. The needed confrontation with a Dragon -who obviously won't part with his scales on his own- negates most of the uses of the boots.
In Ultima Underworld I, the Avatar came into possession of dragon scales and some special thread. Bribing the exile Marrowsuck on the fifth level of the Abyss with enough Fish, he promised to make the boots for the Avatar. Marrowsuck held his word, and the boots proved to be very useful. In Ultima Underworld II, Kintara offered such boots as well, but they were fake (the Leather Vest of Flameproof has to be used instead).