Is it proper to use Tagalog?

I saw this on Tumblr just tonight:

And this reply as well:

WAIT! This is wrong; Filipino is our national language, Tagalog is just a language of central and southern Luzon and northern MIMAROPA; there are distinctions between the languages. Filipino, designated as our national language, is designed to take Tagalog, Cebuano and other Philippine languages as well as foreign words “Filipinized” as basis.

When Erap was sent into a trial and he wished to speak in Tagalog, the court dismissed him saying that Filipino is our language as Filipinos.

Alright, what's the difference between Tagalog and Filipino? Back in 2009 while I was in a training for National Press Conference (NSPC) in Tagaytay, my co-feature writers and I discussed this. We had agreed on Martha's answer that Tagalog is a DIALECT while Filipino is an OFFICIAL LANGUAGE. As for this matter, I think it's not wrong to say "I speak Tagalog." What if that person can only speak Tagalog and not the other dialects in the Philippines? What if someone ask him what language he's speaking and he answered "I speak Filipino." and again he was asked if he can speak Visaya, Ilongo, etc. and he doesn't know? I am in a strong will that this is fine to use for distinction and clarity. Isn't it annoying how sometimes some Filipino ethics are too strict?

You, what do you think? Is it proper to use Tagalog? Or we should stick to using Filipino?