Hi Adrian, many people get nervous about driving abroad. IMHO America is one of the easiest places to drive. Granted driving on the other side of the road takes some concentrating, but all the cars are automatic so you don't have to worry about changing gear (but winding the window down instead
) . You can get the smallest type of hirecar (usually the size of an escort) for about £150 a week inclusive of all taxes.
While staying on I-Drive getting to the parks in that area ( SeaWorld, IOA and US ) is pretty easy and it would give you a chance to get used to the road system and get to know the immediate area of your hotel. The potentially more difficult part is getting to Disney without a car. While there are bus services and taxis available this is either going to be time consuming, relatively expensive or both. Often after a long day in the parks the last thing you want is to stand in the sun waiting for a bus or taxi.
IMHO you have two options (other than your current one of Idrive and no car),
1) you can see if it's possible to split your vacation and spend one week staying on site at Disney and one week on I-drive. If you DEFINATELY don't want to drive this is going to be the easiest option as Disney have a fantastic transport system that means you don't have to drive at all and there is no real inconvenience. There will be a cost to this, but Disney has some good deals on it's All Star resorts and it may not prove as expensive as you think. It's likely the rooms would come with your Disney passes so factor in the cost of a 5 day hopper plus ticket ( probably your best choice) to see if it looks reasonable value to you.
2) Stay with your booked accomodation and take a week doing I-drive attractions getting yourself orientated at least to that area. Book one weeks car hire ( it's going to be MUCH cheaper to do this from theUK before you go) in the smallest car they have. That car will be big enough for a family of four if you're just driving around to the parks and a bit of shopping, plus there is a good chance they won't have that car available and will give you a free upgrade. These companies only keep a minimal number of the smallest cars and will try to "upsell" you to a bigger, flashier car. If you're in any doubt the car you've ordered is sufficient, ask to see the original car BEFORE you upgrade. There's a good chance they'll upgrade you anyway
. It's going to be much easier for you to get to and back from Disney in a car than having to wait for busses. I don't know if you have kids, but they can get fractious at the end of a long day. It can be stressful to have them screaming or crying in a car for 20 minutes, but that's multiplied by a factor of 10 if thats for an hour and it's on a bus ( by a factor of 20 if it's someone elses kid and it's an hour on the bus LOL). The other big plus, IMHO for a car is if you plan to do any shopping ( a big draw in Orlando) unless you want to be carrying ALL of your purchase around ALL DAY, then stumbling about on a bus to get them home it's going to make life far easier if you have the ability to drive to the various malls and outlets. Many of the shops and outlets are spread out over a reasonable distance, while in the case of Belz, it is theorettically possible to walk between the different shops and buildings, in summer it's going to make the experience an unpleasant one.