They are easy to remove. When you unscrew the hub nut (52mm socket required), the outer taper bearing will pull out easily. The disc/hub assembly is then free, but you need to unbolt the caliper and lift it up to clear the disc. The inner hub bearing and outer seal can be left untouched unless you are going to replace them. You need a 13mm 12pt socket to remove the caliper bolts and 14 mm to remove the bolts securing the disc to the hub.
Do a search for more information, there's a lot of stuff on line via google. BTW this section is for the TD5 engine only, not general servicing.