Good free spyware/malware repair programs

[RICHMONDBENGAL_07]

I've got a question to for anyone that may Know.

I'm using a HP laptop that I bought about 2yrs ago.  I guess It had Norton antivirus software already installed on it when I got it.  It keeps telling me that it going to expire soon and that I should renew it.  Now I haven't had any problems with it, but I've heard Norton is crap (I have no idea though). 

So should I renew it?  Is it free to renew? If not, how much? Is there a better alternative?  Any suggestions?