As others have pointed out, the Hubble and ISS are in very different orbits. The Hubble's orbit is inclined about 28.5 degrees from the equator and the ISS's inclination is about 51.6 degrees. It'd take an incredible amount of propellant, far more than the Shuttle can carry, to move the Hubble to the ISS's orbit.

The Hubble is a large satellite with a mass of almost 11,000 kilograms. It was launched into a 28.5 degree orbit because that's the minimum orbital inclination you can launch directly into from Cape Canaveral. That's also the inclination where you can launch the greatest payload to the highest orbit with a Shuttle.

The ISS is in a 51.6 degree orbit because of our Russian partners. 51.6 degrees is the lowest orbital inclination you can directly launch something into from their main spaceport due to their high latitude and ground safety limitations.

Even if you could find a way to move the Hubble into the same orbital inclination with the ISS, you'd still have to match orbital plane. Perhaps the only way you could move the Hubble would be for a Shuttle to deliver an Inertial Upper Stage to the Hubble, attack it, and use it to do the job. I don't know if an IUS has enough power to do it but that's about the only Shuttle-rated vehicle with any hope. An IUS can lift a 5,000 pound payload from the Shuttle's orbit to geosynch, both raising the altitude and lowering the inclination. It just might have enough energy to move the far more massive Hubble to a compatible inclination with the ISS since it wouldn't have to worry about changing the altitude very much. However, there would be substancial integration issues. The Hubble was never designed to be boosted in this way and you might destroy the optics or damage the other systems when your fired the IUS.

Even if you could do that, there's another problem - contamination. The Hubble has no propulsion system because they don't want to contaminate the optics with spew from the thrusters. If you could move the Hubble close to the ISS, you'd have to be concerned about the possibility of contamination from the ISS's thrusters. When a Shuttle is approaching the Hubble on a servicing mission, they close the Hubble's lens flap to protect the optics. You wouldn't want to do that every time the ISS needed to fire its thrusters or was handling an arriving Shuttle, Soyuz, or Progress vehicle.