computer is acting weird

i have hp xp and the highest internet service and my computer has been slowing down and crashing alot ihad added a nother user recently thought that might be the problem so i got rid of it that made it a little better and spybot has not found anytrhing on my computer weird!!!!!!!!!!!!! when i restart my computer i get the message smart failure predicted on hard disk 0: maxtor 4r080l0-(pm) warning immediatly backup your data and replace hard disk drive a failure may be immenent press f2 to continue .. is this really necessary?

When you get a warning that your hard drive might imminently crash, it's ALWAYS better to be safe than sorry! Making backups is something everyone should do regularly. Recovery after a crash is way more difficult if not impossible.