I have AVG Internet security, i also have Spybot, I have Ad aware profesional, Malawarebytes, tune up utilities 2009.

Is there such thing as having too much security that your computer might be actually more vonerable to threats ?? what i have notices myself is that my system does run a little slow could this be because of too much security ??? also what is a good combination of security programs that won´t slow your system too much.