John, you asked about using such scales in combination with one another. Allow me to explain my point of view, beginning with some fundamentals (I am going somewhere with this):

The three major modes are Ionian (1st), Lydian (4th), and Myxolydian (5th).
So, in the key of C one might be expected to play C Ionian over a C Major chord, F Lydian over F major, and G Myxolydian over G major (or G dominant if you are adding the b7).

The three minor modes are Dorian (2nd), Phrygian (3rd), and Aeolian (6th).
So, in the key of C one might be expected to play D Dorian over a D minor chord, E Phrygian over an E minor chord, and A Aeolian over an A minor chord.

ALLOW ME TO BLOW YOUR MIND FOR A MOMENT:
The Minor Pentatonic Scale (penta meaning 'five') contains the following intervals: 1-b3-4-5-b7
What you'll notice is that each of these intervals are included in the minor modes, with the addition of two notes:
Dorian: 1-2-b3-4-5-6-b7
Phrygian: 1-b2-b3-4-5-b6-b7
Aeolian: 1-2-b3-4-5-b6-b7

What this means is that when you are playing any of Dorian, Phrygian, or Aeolian.. you are playing the minor pentatonic scale with the addition of two notes to establish a new tonality. YOU CAN PLAY THE MINOR PENTATONIC SCALE IN ANY OF DORIAN, PHRYGIAN, or AEOLIAN, should you choose to isolate these notes! Feel free to add some extra notes of the modes to your pentatonic licks to add some new, tasty flavour.

You also asked about the Blues scale. I assume you are meaning the minor pentatonic scale with the addition of a b5... the b5 is more for the sake of adding chromaticisms (consecutive half steps). These are popular in many forms of music, especially jazz but especially blues. Consider it another spice to you can go to.

There, my best goranm impression.