Which one to download?

Hi, I have had folding on my computer before (ages ago) and now I have a new computer so what I was wondering is If the SMP is for 24/7 computers, which one is best for non 24/7 ones, does anybody have a link to the correct one i need?

Also, last thing I remember was that when I ight clicked the icon in the task bar, all I got was a animated graphic of the unit but no details (how much had been done, time to finish unit etc) how do I get them to work again too?

many thanks,

Ben