yes...tesco are good for their giant hams.
I usually boil mine and then glaze it
pan of water, peppercorns, swathes of herbs, cloves, quartered onion, stick of celery, apple maybe, bit of orange zest ( Itend to go through the spice basket an hurl in what takes my fancy)
dunk ham in and put the lid on, and bring up to the boil, I usually then throw that water out just in case it is a bit salty and scummy
replace with clean water/cider/apple juice/coke/dry ginger whatever you feel really...you should still have all the gubbins so set them into the bottom of the pan as well and let it sit at a really low simer
Once it is about half an hour from being done then I drain it (keep the stock for soup), peel off the icky skin, but leave a good layer of fat...now is the time to mark squares and criss crosses and poke in cloves if you want them and then cover it with something sweet and sticky honey/marmalade/maple syrup/brown sugar/dod of mustard/blob of chutney and give it half an hour in a fairly hot oven.
Lock the kitchen door if you have to leave it to cool otherwise people will pick bits off just to try, it smells AMAAAAZING and then you will have nothing left but a bone.
I tend to pick a theme and run with it...so coke means a spicier backbone to the herbs, and a more neutral sticky glaze
orange peel in with the stock then go marmalade and maybe ginger, dark brown sugar for the glaze
cider for the stock, hurl in a cinnamon stick too, and go syrup, apple juice, wholegrain mustard and cloves for the glaze.
We buy a really big joint, with a bone, and have hot ham rolls for Christmas Eve supper and then the rest for cold cuts.