You must try Scottish Whisky, and there's no shortage of it in Glasgow.
Whilst on the subject of food and drink try Haggis, don't be put off by the ingredients (unless you're a veggie) if it's served well you'll wish you had tried it sooner.
Beware of too much fast food, the Scots have a pretty fatty diet, so if you're going to indulge yourself, make sure you're just staying for the weekend.
Visit some Scottish whiskey breweries. An opportunity to see the making of whiskey and later on taste some of it.
Visit the home hills/plains of some Scottish heros such as Rob Roy or William Wallace (a.k.a Braveheart).