As I mentioned, Odile is the point of contact for international students in the maths department. She is very helpful, although if you need to speak to her make sure you go well in advance as she is sometimes hard to locate. You can find information about the course at http://www-fourier.ujf-grenoble.fr/enseignement/spip.php?rubrique40&lang=fr.
There are two streams within the year for maths; Parcours A and Parcours B. I was in Parcours B, the easier of the two streams. In terms of modules, there isn’t a large selection. In the first semester I took Topology and Algebra along with the other students on Parcours B. The content of these modules is fairly similar to that seen in second year at Warwick and is taught through lectures (some of which were two hours long; a bit of a struggle to start with!) and seminars. The exams for these modules are in January and I found that the content of the exams was in contrast to that which we had learnt throughout the year and so I struggled.
In the second semester there is some choice of modules. I decided to take Integral Calculus and Differential Calculus and then I took some French courses, aimed at international students. I would highly recommend the French courses, taught by a great lecturer Jean Guichard at the University of Stendhal. I took French Grammar and Professional French which I found really useful. There are also translation classes in several topics. These courses can be taken in both terms and I would definitely advise taking some in the first semester. In order to take the modules it is necessary to register at the University of Stendhal, but this is fairly straightforward.
As well as the French courses there are also some French language evening classes that can be taken for credit. You should be informed of these by Odile and then take a test to put you into a class. These classes can be really useful, both for language and for learning about the French culture.