I've bought loads of DS games and plan to buy more in the future but ive decided to invest in a flash card so i can use it to store other things, basically need some advice on which one to get?

I was thinking about this one

http://www.memorybits.co.uk/shop/sd-gaming/r4--nintendo-dslite-adapter-/5907

but i honestly have no idea on how the whole thing works, do i have to do anything to my ds to get games to work on it? and is it easy enough, ie drag and drop them onto your flash drive and just plug and play into your ds?

thanks