Why Is My Computer Running Slow

I think there related but when i type every 45 seconds or so the writing types real slow and then speeds up again after about 15, also i found out while playing a game that if i click while it is going this slow, my computer will beep as many times as a click when it speeds up agian.
also. i bearly have any processes, i got dell inspiron 1501 and this only started happening recently.

Can’t do anything with the computer. It has all sorts of virus and any website you type on the address bar leads to the same website again and again. Tried to use a virus program through a CD but the CD drive itself was immobilized and what comes up after popping the CD is the same website.