[People should not vote if they are not an informed voter.]
I have to disagree with you.  First off, who is an objective enough judge to determine what is or is not an "informed" vote?  Secondly, the democratic system we rely on functions best when everyone participates not just the 20% or so that turns out for the local/primary elections.  Next, a good portion of those are merely voting based upon party rather than information.  By your suggestion we'd see maybe 2-5% of voters turning out.  Also, uninformed voters, statically speaking, should be a wash so they aren't likely to be a deciding factor anyway.  Finally, I just simply have to disagree with you a more fundamental level.  Any vote is a good vote so long as it is cast in good faith.  While it is preferable to cast an informed vote the fact that one's information is limited or the voter is apathetic in most political matters doesn't make his/her participation any less valued or any more unwanted.