These are the modules studied in the first year:
http://www.ntu.ac.uk/apps/pss/course_finder/103827-1/39/BSc_%28Hons%29_Mathematics.aspx?yoe=5&st=2&sv=M&sl=2#course'Algebra' could refer to lots of things in maths. As well as the x+y=z stuff you're used to, it can also refer to vectors&matrices stuff (this is called linear algebra) and it can also be something entirely new which is where you generalise the whole concepts of addition/multiplication and consider what happens e.g. when there are only finitely many numbers out there instead of infinitely many.
In the first year, the algebra would most likely be about vectors and matrices. Since they don't require further maths then this would probably mean going over the FP1 stuff again.
'Computational and numerical methods' would most likely be about getting an approximation to an answer when you can't solve it directly. This would probably include e.g. Newton-Raphson whixh would require your differentiation skills to be good.
'Foundations and Investigations in Mathematics' sounds like the type of course that would introduce you to university maths, covering lots of little topics and getting you used to proving things. If you've done induction then there would be more of that sort of stuff where you have to be quite formal/precise in your explanations.
'Mathematical Methods One' - I'm not entirely sure what this would involve.
'Statistics One' - This would most likely be covering similar stuff to the a-level stats modules, but with a more rigorous approach. Since none of the stats modules are core then they can't expect people to already know this stuff. However, there would probably be some differentiation/integration involved here so make sure you're strong on those.
'Vector Algebra and Calculus' would probably follow on from Algebra One and would involve differentiation/integration but with vectors.
Oh and also complex numbers would probably come up in some of these modules.
So overall, the most important thing would be to make sure your differentiation/integration skills are good. C3/C4 would be helpful here. If you're able to sit a past paper in each of those and get a B then you'll know you're good enough for the course.
Looking at FP1 (particularly stuff on matrices, complex numbers and induction) would be helpful but not essential. If you have time then you could always look at S1 but this isn't really necessary.
With regards to the other FP modules, although some of their content would probably overlap with what you do at uni it is quite a bit beyond the maths a-level material so they can't really expect you to know it.