Dinner on a rainy weekend

We'll be having some friends over this weekend at the cabin, since it seems like it will be raining ALL the time, Jonas and I have decided on making a cozy meal.  We have two options:

 Jamie Oliver's Roast Pork Shoulder

 or... Roast shoulder of lamb (also Jamie Oliver)

 I am not very experienced cooking meat, so I need a guide, and who else than Jamie Oliver to give me a easy to follow, down to earth, 100% pleasing recipe?  I know, I am a big fan, and I have always been, but I have never been let down, and I have learned a lot about cooking from him, so, when in looking for a good recipe full of flavour, that's my man.

I'll tell you how it went!