I lived in Malta for 5 years and don't think I saw everything...amd that is saying a lot considering its about 21x7 miles.
You can get around by public bus dirt cheap. Valetta is the bus hub. Driving is dangerous, but if you attempt it, get something very small, possibly even a motor scooter. Gas (petrol) is expensive and traffic can be hell. Don't let this discourage you. You can get anywhere on the island in 1 1/2 hours driving.
Anyhow... Places you'll want to see:
(medevil fortress city) - you'll only need about 2 hours to see the entire town, its not a big place. Plan to eat here, romantic views. Check out the cathedral. If you go no where else, this place is amazing!
- capital city, fortified in 1400s, some shopping, lots of museums and places of interest. Make sure to check out the public gardens, also walk all the way to the tip of the peninsula and check out the coast and the fort.
- for shopping and nite-life - go on saturday night and plan to party!
- these are small fishing villages down south...worth taking time and walking around. Lots of photographic scenes!
- take a day or two and go to the other major island, it has a lot more country side and is much more laid back and well beautiful. Go to Rabat and see the cathederal and walk around the small towns. Also go to the Sea Window and Fungi Rock.
Other must see
places of interest:
- there are several of them. Go to as many of them as you can, they are one of the most amazing things you will ever see.
- beautiful views. Some neo-lythic temples are near by.
Witt Bobbu/Blue Grotto
- (Witt=valley.) Its off the beaten path in the southern cliffs. There is a valley that is basicly a crack in the cliffs. You have to go down ancient stone farmer's stairs, and not many people know about it. To find it ask for the Blue Grotto. Blue Grotto is effectively at the end of the valley on the North side, so you would have just driven along side the valley. If you enjoy hiking this is the palce...its life a Mediterrainian garden of eden. Hike all the way down to the sea and you'll be able to see the rock formation that is the Blue Grotto and Filfla, a small island off the coast.
St. Pauls Bay
- this is where you'll want to go if you want to hit up a sandy beach an work on your tan. Its touristy though, and can be crowded in summer-time.
There is so much more, but these are key things. I might think of more latter... If you have specifc questions or interests let me know. My main piece of advice is to walk through small towns. Eat at little hole in the wall places, etc. Its a laid back place. You'll love it!