That's the magic of the Lagrange Orbits. They're very cheap to get to from an escape trajectory, but they hang around the body(ies) that they're attached to.

That's where the "Strategic Spots" come in. There are certain points along the orbit from earth to X (moon, mars, asteroid, etc) where it would take extremely little thrust from the space ship to drop by there (stop is the wrong word).

Also, as others have mentioned, it would be possible for the "Gas Station" or at least a module of it to come to you as well.

You pretty much nailed it all on the head. The only thing that I wanted to add was that there has been one probe to move between two massive bodies (Earth and the Moon) using a continuous thrust system: the SMART-1 probe with its Ion engine. The downside: it took 13 months (it only took the Apollo astronauts a couple days) and used a series of really strange, constantly expanding orbits (basically a spiral), on the plus side it only took 1/10th of the total propellant mass that a chemically powered spacecraft would.

Ion/Hall/Plasma thrusters are great for moving cargo where you don't care too much about how long it takes (especially in the beginning of the mission). This type of technology could easily be used to move fuel to one of these "Gas Stations" in earth, moon, sun, or mars orbit. You could start this years before the need date (before you get busy testing out the manned space craft) then the chemical fuel could already be there when you're ready to launch the manned space craft.

That Discover article was pretty hit-or-miss. They nailed the real solution in two of their pieces (tethers and sails), in that the best (easiest, cheapest, only-one-that-will-probably-ever-happen) are technologies that are built into space objects (satellites and boosters) before launch. There's lots of options here from tethers, sails, balloons, or just using existing thrusters. If we can stop leaving big pieces up there (which can run into other big pieces and make LOTS of pieces), the problem will start getting less severe.

On the other hand, on of Discover's pages was about blowing up the debris...this makes sense, until you really think about it. The problem is that when you blow up something, it makes a huge number of new pieces, with all sorts of different velocities and orbits. On average, these pieces will fall to earth more quickly than the unexploded satellite, however, that's just the average. There are many pieces that will stay up there even longer. And when you're talking about things moving that these incredible velocities, it doesn't matter a whole lot if you get hit by a 6,000lb. satellite or a 5lb. piece of a satellite, either one will destroy anything we've put in orbit.

A few ounces of force isn't much as most satellites experience hundreds or thousands of pounds of force during the launch. Since you're trying to de-orbit the satellite, you probably don't care too much about what attitude it is in, so as long as the part of the balloon that attaches to the satellite is capable of handling those few ounces of force, I'm not sure what else there would be to go wrong.

No, it will be dragging behind the satellite, in the lower density area that has been swept out by the satellite. Because this area is lower density, it won't create as much aerodynamic drag as it would if it was perpendicular to the path of travel.

Also, the big stuff (many of which are rocket stages with some fuel left in them) sometimes explodes: http://www.newscientist.com/article/dn10979

If we can deorbit even one *before* it explodes, we can cut the number of space debris by hundreds or thousands.

Quite easily. Well, moderately easily...most normal GPS receivers would work in space except they have an arbitrary limit of 60,000ft and Mach 1 (?? not sure of the exact speed off the top of my head) that keep them from being turned into guidance systems for ballistic missiles. GPS is already routinely used for spacecraft navigation, you just need a more expensive receiver without the imposed limit.