Primers are great if you want your makeup to go on smoothly and stay put. For my makeup clients with dry skin I use a Laura Mercier one, it's lovely; for brides I use Smashbox as it has good staying power. Korres (available from Kit Cosmetics) has a nice one with no silicone, parabens etc if you have sensitive skin.

To be honest I think BB creams are over-hyped. You'd be better off getting a good tinted moisturiser I reckon. Again Laura Mercier ones are nice (exxy though), Benefit's You Rebel, Aveda (LOVE) and on the budget side there's a Revlon one I like but can't remember the name...

With regard to sun protection, would also suggest a product that has broad spectrum SPF or using a separate cream underneath any kind of base; the SPF in moisturisers, foundations etc doesn't really cut the mustard for our climate. Invisible Zinc Tinted Daywear is a good multi-tasker.