Haven't stayed there, or even heard of it (you don't say where it's located, but I think somewhere further down the west coast?), but it gets a range of reviews on TA, many very good.
You have access to some great coastal scenery on the way up the west coast to the north. However, the route isn't all coastal, it's winding, and this will eat into your journey time (as well as give you some different scenery). The roads going north from Paleokastritsa (some great viewpoints in this area) shoot up through some tremendous height then head off again north-west.
For a rough idea see
http://www.allcorfu.com/i/maps/big/corfuroadmap.jpg

There're a few suggestions for driving/places with good scenery here
http://www.carhire4corfu.com/nwcorfu/north_west_corfu.html

Your car rental company should provide you with a usable map, denoting the better roads (supermarkets will also sell road maps). When negotiating hire and ask them about routes. It's in their interests to not have the car undercarriage wrecked and give you reasonable advice. Carry your licence with you at all times when driving.
I can't recommend a car hire company as I just look around what is on offer. Price isn't the only feature I'm looking for, but level of insurance too. Collision Damage Waiver limits your liablilty in the event of damage in a collision, but can give you quite a high excess. Look for Super CDW to lower that liability. Check your excess limits for prices quoted, some of them can be quite jaw-dropping.
Sorry this isn't an awful lot of use in terms of times etc., I just get in a car and explore, and don't mind too much where I end up (as long as the road doesn't get too rough). I'm always getting lost and turning back when I end up on dead-ends or bad road surfaces, so can't give any realistic timescales. However, all this is half the fun and you get to see things you wouldn't otherwise see. Just aim to be somewhere near where you're staying before dusk, because the dark isn't any fun and you can't see the state of the roads too well. Views around Mt Pantokrator are quite something. Lucky you, Ed! Nice time of year to visit, not too busy either.

For car hire from and return to the airport I can recommend Top Cars who we have used for several years.
http://www.topcars.gr/

Not only are they one of the cheapest but their terms include full insurance with NO excess (in case of damage).

Just reserve the car by email and they will meet you at arrivals.

Dennis

Thanks Phoebe and Dennis for your replies.

I have booked a car from Top Cars it was 120 Euro for the week, pay cash on arrival no card number required and no cancellation fee if I cant make it so seems a good deal when you look at the cost and time needed for a coach or taxi transfer.

I will be looking for a good map before I go as TomTom want £39.95 for a Greek map.

Ed

Ed

That IS a good price for a week. No maps for Corfu are very good and the ones supplied with a car hire are pretty useless. In 18 years I have found that the best one for road travel is by 'tc Travel maps' scale 1/80000 which is usually on sale at UK airports at aboout £5. Otherwise buy it over there.
It has a bright red cover and is titled 'Korfu Corfu'.

Aquis Sandy Beach is in Agios Georgios (southern one) compared to 'Agios Georgios north' as mentioned on the 2nd web-site quoted by Phoebe. So it is quite a long way south (if anywhere in Corfu can be along way).
One interesting drive for you would be along minor roads north of AG via Gardiki then hugging the coast to Agios Geordis, Glyfada etc.

It would really need a separate day to visit and do justice to the north-west viewpoints and resorts of Paleokastritsa, Vistonas, Agios Georgios north, Afionas, Agios Stefanos NW, and if you have time the cliffs of Peroulades in the top left corner of Corfu island.
http://www.agiosgeorgios.info

Dennis