Zoe's apartment is a great place to stay in Valletta. It's about a 5 - 10 minute walk to the bus station (here you can get a bus to pretty much wherever you want to go in Malta). You are within walking distance of shops and restaurants. If you stay here over the weekend, be aware of the noise - Zoe's apartment is above two bars.
I would highly recommend staying here and look forward to the next time I'm in Malta! :)