I think it's a good idea to take yourself off to somewhere like PC World or John Lewis and try various mice and keyboards for yourself: what one person loves another might loathe, so it's not really something that anyone can advise on.
Microsoft makes a range of multimedia keyboards bristling with buttons which might suit you.
One thing I would say is avoid the temptations of wireless keyboards and mice. They eat batteries and can be flaky. Good old-fashioned wires are nice and reliable.