Where do you buy your accessories?

If the Disco will be a daily driver than I'd avoid doing any heavy modifying. A good 2-3" lift from OME or TerraFirma will actually improve road manners (less corner lean and squat, improved dampening) and will get you damn near anywhere offroad. You can add tires to the package but keep in mind that you'll lose low-end torque (big tires gear it up) and take a hit on gas mileage, not to mention the addition of road noise.

Bumpers, winches, and roof racks are heavy and expensive and aren't really necessary on a road car. If you want the "look" of an off-roader you can install an a-bar and some running boards. The running boards act as nerf bars or rock sliders and will keep the car free from most light trail damage and the A-bar will protect the radiator and front end from minor bumps. They won't help in anything major - 5000 pounds of metal has a lot of momentum. They're much lighter and more affordable than a full steel bumper kit. Used parts show up all the time.

The best thing you can do for any offroad adventures is to get your car in peak mechanical shape. Plugs, wires, an air filter, and quality oil do wonders to improve the grunt you need to get around obstacles, and fixing the Three Amigos (if you have them) is absolutely paramount. You won't get many places with your ABS and TC disabled. A cooling system upgrade with a low-temp thermostat and green fluid will ensure everything stays nice and cool on the trail.

I have an '03 SE with a "Medium Duty" TerraFirma lift and street tires and I've been all over the sugar sand trails and mud holes of north Florida without so much as a hiccup. Skips through them like a mountain goat.