How to remove a memory stick from your desktop?

i have a dell dimension desktop E310 and one of my memory sticks is not compatible with the new one i had installed and i did not install them and although the person who did tol me it would slow down my computer i didnt know it was goin to slow it down drastically so i was wondering if i simply just removed the stick out of the slot would i damage anything or is there more to it than that?