Coolangatta is right at the southern end of the Gold Coast. The touristy things are mostly at the northern end of the coast, at and near Surfers Paradise and Broadbeach, about 20 or so miles north of OOL airport (20 to 40 minutes depending on time of day and time of year). So if you do go, plan on transport north to where the action is.
However, if you are just wanting a nice beach to swim and soak up some Queensland sunshine, then there are plenty of beaches and accommodation closer to the airport, a cheap taxi ride away. If staying overnight, there are lots of great places to eat and all sorts of entertainment. But unless you are staying in Surfers Paradise, you will probably need transport.
OOL is only an hour flying time from SYD, as in BNE. BNE and OOL are similar time from Surfers Paradise, though OOL is less distance.
Its a pitty you don't have more time, since there are lots of things to see and do on and around the Gold Coast, so choosing what to do in a single day will be hard, and will depend on what you enjoy doing most (shopping, lazing on a beach, theme parks, bush walks, nature reserves, etc).
Again, depending on what you like to do, consider visiting Currumbin Wildlife Sanctuary, which is only about 10 mins drive north of OOL and very near the beach.
__________________ NM aka Nelly Mobbs
Go directly to WHY, do not pass F, do not collect a J amenity kit.
I think it really depends on what you're looking for. Specially with only 4 days to spare, with some portion of that likely involving getting over the flight here it boils down to what you want to get out of your trip. For example, if you want a warm beach and some sun, then sure OOL would be nice, or even Sunshine coast may be warmer still (CNS might be too far!). If you're after nightlife, entertainment, comedy, theatre, music etc, then Melbourne would be a good alternative to SYD, but perhaps 2 cities is a lot to take in, so OOL might be a nice diversion. BNE might give a bit of both - you can get to some beaches from there, but it also has nightlife etc.
Again, it all depends on what you're looking for from your visit.
Of course, I think you should come to MEL, but that's just personal
RichardMEL, UA 1K
A Star Alliance Member.
Tough decision... I've been to OOL twice in the last year and can definitely recommend the visit. You can fly in mid-day, take in some activities such as one of the various wildlife parks, stay at the Sheraton Mirage for the evening buffet, get up early in the morning and take a long walk on an almost deserted beach watching the sun rise over the pacific, go back to the hotel for the - just as large - breakfast buffet (or go for a workout at the newly refurbished health club) and head back to OOL. Plus short field operations in a 767 are sort of cool also!
As much as I like Melbourne, I wouldn't recommend it for just one day. In my view, it is a more complex and interesting city than Sydney and requires more than a few days to explore the nooks and crannies.