also, should I leave the net thing on the meat when its in the oven?

I take the net off. I just bung it in the oven at the required temperature and cook for the required time. Sometimes I put little knife crosses into it and shove in garlic gloves and shake herbs over it and rub some oil into it.

Yes leave the net on. I'd cook it for 20 mins at the highest heat to seal and sear the meat and then turn the oven down to about 180 degrees and cook for about 20 mins per pound (450 grams) turning it up again to maximum heat for the last 15 minutes.

Or cook it much longer at a much lower temperature.

thanks all, just one more question, do I need to turn it over or anything during the time its in the oven?

No, you don't.

Make a rub for it, loads available on the internet, then cook it low and slow for 6 hours or so, voila, pulled pork.

I cook Pork on a high heat for 20 minutes then low heat for the rest of it's cooking time, after the first hour of cooking, i use a meat thermometer about every half hour to check if it's cooked, Pork is cooked when the juices run clear, but you might want to check more often if your using smaller joints of Pork.

A load of root veg & garlic, a glass of white wine, sit the pork on top, cover tightly with foil, bung in a low oven for 4-5 hours. Remove the pork to a warm plate, add a bit of stock to the veg in the roasting tin. Bring to a simmer then pass it all through a sieve, season and serve with the meltingly soft pork.