enabling hidden programs?

i just picked up my Aspire 1 today from PC World, they had it for £199 which i thought was a good price

anyway im very new to linux, but i am enjoying it so far, ive been reading all afternoon and managed to get things like VLC installed and have the icon appear under the Fun tab, also enabled that advance desk top

i notice there are useful programes like the task manager equivalent system monitor and another for the screen saver... is it possible to get these icons put under one of the 4 tabs as well? system monitor would be good. i like to see whats going on (i never knew these atom chips were dual core either?! is that right?)

also, how do i change themes? i downloaded a load to the emerald thingy using

sudo yum install emeral-themes or something like that....but how do u actually activate them? also i have seen how to activate compiz, but how do i turn it off if i dont like it?

thanks!

 

System monitor, no need for a menu................
just use ctrl + alt + del