Fast DDR or More DDR

[WatchTower]

Is it better to have 4Gb of say Corsair Value memory expenisve memory made for those that like to clock? I already have 2gb which is great I found a lot of memory helps when in an mmorpg and there's like 60 odd or more players on your screen at once.

 

[WatchTower]

Will it help when I'm creating DivXs or using PaintShop Ele 4? I've also read that the next windows will need aleast 1Gb to run at its best.