I agree with Culzean, 5w-30 is probably the best compromise between viscosity and wear protection, and because it's a popular grade it's that bit cheaper.
Any quality brand is ideal, but anything that is graded SL/CF or better will do the job. Fit a decent quality filter too, genuine Honda, Meyle, Hengst, Fram, Mann, etc.. Avoid ECP's cheap Crosland branded filters.