I have not read The Name of the Rose but I have seen the movie and thought it was very good too. It is on my mental 'to read someday' list.
I had high hopes for Baudolino. It began well. The first few pages that introduce the book and the character of Baudolinio were enchanting. He was a young rascal learning to write in Latin and trying to write his autobiography.
Then the story moves forward to his years as an adopted son of Frederick Barbarossa, through the disastrous Third Crusade and sack of Constantinople, as well as the Holy Roman Emperor's difficulties in bringing the Italian city states to heel, and Paris in the 12th century. Eco does 'period' very, very well but then the trip to find the legendary Prester John begins.
In English, the novel is 521 pages long. The trip to the East to find the priest/king begins around page 316 and for sixty pages, Baudolino and his group struggle through a landscape that is very reminiscent of Swift's Gulliver's Travels and is taken partly from Pliny and partly from the letter from Prester John to Manuel I Comnenus, the Byzantine emperor, and from Otto of Freising's chronicle as well as other sources. This trip to the East is said to have provided Wolfram von Eschenbach with some of the details of his Parzival.
Baudolino travelled East with Kyot, who was supposed to have given the story of the Grail to Wolfram. There are several other historical figures travelling with Baudolino like Zosimos, an Arab alchemist, Robert de Boron, and the Archpoet. You could skip over much of the travelling. It is like the camping trip that never ends in Harry Potter and the Deathly Hallows - a big snore.
For another 80 pages, the travellers linger in the East getting to know the fabulous inhabitants and debating theology with them. That was like those long discussions of nihilism in Dostoyevsky - you can skip over much of that without missing anything related to the story. Of course, if you want to read more about gnosticism and other 'heresies', read on. Then there is the flight back to the West and the arrival at Constantinople in time to watch it burn and to meet Niketas Choniates and tell him the story. You could skim over almost 150 pages without missing much in my opinion. Otherwise, it was good; I enjoyed reading about the wars between Frederick and the Italians and the story of the Third Crusade. Eco can write an engaging story without having to tweak the facts and I like that most of the history in the novel is accurate. I say most because there is no Baudolino.
One thing to add - Eco translated the Latin for this novel which will make some people very happy.