50 f/1.8 is a given. Great lens, great for learning the principals of photography, also v.good emergency go to lens in low light. You might as well edit the question to be "50 f/1.8 plus what other lens for £430"
- I'm going to bend the rules a little and say you should get the 50/1.8, kit zoom, Canon 430EX flash. That should come in under £500.
This should cover a wide range of shooting options. The reason for including the flash is that most people I know who have bought a DSLR for the first time tend to be used to shooting indoors. Learning to use a flash properly in this situation can be the biggest thing you do to improve your photography. The other sort of shooting people do initially is nature/landscape which is handled by the kit lens, which performs ok stopped down.
Failing that forgetting the flash replacing the kit with a superzoom as you suggest is an option, though personally I think people will get too comfortable with it and never change lenses, which is missing out on the point of a DSLR.