Peace!

I have a 700MHz box with a 256MB RAM and a 40HDD. Why do I feel like it is very slow? I feel that applications take ages to run and I feel lots of unnecessary processes work in the back ground. I used top to see what is there, but I find it very hard to see which ones should I kill and which should I leave working. Can you help me?

PS. Even for a better box with the latest Processor, I find the problem persistent, why? I have heared rumors about KDE being slow, but I am a lover of this graphical environment. What should I do? and if you use your box mainly for doing programming and compiling things with some net actions and emailing, what would you do?

M B