New South Wales
Can any character equip and carry weapons and/or spells and if so can they cary a melee or ranged in one hand and a spell in the other?
Sure. They can only use one of the weapons at a time, though, unless they share the same name and have the dual wielding icon.
Also can a character carry a great sword (for example), which I assume is a two handed weapon, in one hand and another weapon in the other?
Yep. There's no two-handed weapons.