New to the forum.

I have Inspirion 1545 about 2-3 years old.  Web browsing, keying in web browser has become increasingly slow.  I noticed some of the icons on my favorites list has changed.  Alot of times letters are missed when I am keying.  Running non web browser programs are fine.  I use Norton and it doesn' t detect anything.  I suspect I have some sort of malware/spyware.  Can someone help me on this?

Regards