Linux has ( imho ) better memory management ( Desktop environments excluded since I have noticed memory leaks on some applications, but those can be restarted on the fly anyway ) but even then you are not really taking too much advantage of more than 1 core anyway if you are not using at least 1 gb of ram but more likely 2 gb.

Adding more ram will make a huge difference for your system, more processor will just fill up the bottleneck faster and wait, so it would be kind of a waste.