Kristobal

I might be wrong, but I think that's the first stage of Soyuz

I've done the exact same thing, except instead of using up nearly all his fuel, the poor little guy completely ran out! I was surprised I was able to get up so close

Most satisfying thing I ever did was rescue a kerbal from Munar orbit that had zero EVA propellant left. Nothing quite like flying right up to within inches of a kerbal and rotating your ship juuust right

It's easier, although more time-consuming, To rendezvous if the two objects have close orbits. Set it up so that one craft's periapsis and apopapsis are both just inside/outside of the other's orbit. This makes the relative velocity much lower, which leads to a slower rendezvous that takes longer to occur. I'd recommend starting out in an orbit with a larger difference then adjusting it as the distance between the crafts gets smaller.

Once you get within a couple kilometers, set the Navball to "Target" mode (and make sure you have the other ship set as your target.) It will show your relative speed to the target vessel. You can zero your speed by burning on the retrograde marker. Then, aim toward the pro-target marker and burn, trying to keep your prograde on that marker. Once you get close, slow down and make sure to control from the docking port by right-clicking it and selecting "control from here". It also helps to make sure the other ship's docking port is facing towards you so you don't have to deal with trying to circle around it. I hope this helps

My first mission to Moho, I drastically underestimated the delta-V needed. The probe ran out of fuel above the surface, and hit the ground at about 30 m/s, amazingly unharmed. You can imagine how relieved I was