St Julians is a great central location to stay and is a pretty harbour with traditional colourful fishing boats. Hiring a car is a good idea and they drive on the left. There is a good bus service to Valetta and for all other destinations you will probably need to change at Valetta.
Valetta – lovely capital city. Recommend for the architecture and also a must-see are the Upper Barrakka Gardens for a great view of the grand harbour. From here you can see three old cities Vittoriosa, Senglea and Cospicua – you can also see why they were a great ally to defend Europe in the war due the view/defence position. There are a load of new restaurants on the newly done up Waterfront area. Cordina’s café at the end of Republic Street do good cakes/ice cream and you can sit out and watch the world go by. It’s been there for decades.
Rabat/Mdina – ancient cities next to each other and well worth a visit for the architecture. It’s where Malta used to bury it’s dead and known as the silent city. It’s proper ‘old Malta’
Dingli cliffs – for a spectacular view, she should try and get to Dingli cliffs on the western coast if it’s a clear day. It’s the highest point in Malta. It’s a bit of a trek but great view
Beach – most beaches are rocky but if the weather is good enough the best sandy beach is called Golden Bay – you can get a bus there but would need to change at Valetta
St Peter’s Pool – one for the summer really and you need a car but it’s an picturesque secluded giant rock pool you can jump into.
Restaurants – food has improved no end over the last few years but for some traditional maltese food I’d try Ta' Kolina in Sleima – you could walk from St Julians (at a push) or get one of the buses along the coast there (5 mins). I also like Il Merill in Sleima but haven’t been there for a few years.
If you fancy going further afield, Ta' Marija is lovely (although they have a naff 1970s dancefloor in the middle, presumably used later in the night as I’ve never seen it in use!) The food is traditional maltese and I’ve never had a bad meal there. There is a huge domed church round the corner known for a miracle – in WW2 a bomb dropped in the middle of the church service but didn’t detonate and rolled right through the church. It’s there in the church today for people to view.
Avoid Paceville – it’s the disco nightclub area just north of St Julians. Also avoid Bugibba as it’s full of fish & chip places.
Whilst there try:
Kinnie – bitter orange fizzy non alcoholic drink.
Pastizzi – small puff pastry pasty pocket filled with ricotta cheese. Look out to Maxim’s shops that are dotted around and sell them hot out the oven for a few cents. They do a pea version which I am not so keen on.