huh? how can you get no play vertically but have the top move in and out? Sorry, that doesn't make sense, if you have play then you can take off the dust cover and tighten up the nut holding the hub on the spindle. The dust cover is the little hemispherical chunk of metal right in the middle of the rotor and you'll have to use a screwdriver and a hammer to get it off, just tap the screwdriver in around the edge until you can wiggle the cap off. Then you'll have to get a pair of sidecutters and take out the cotter pin, then pull off the lock and you should be left with a big fat nut that will probably be hand tight. Get a pair of channel locks and tighten it up until you feel the hub drag when you try to spin it, then back it off about a eighth of a turn, just so the dragging goes away. Put the lock back on a put the cotter pin back in just how it was before and then tap the dust cover back on, make sure to just tap around the edges as if you tap in the middle and bend it in you may make it touch the spindle and all kinds of bad things can happen. Once the cover is back on you're all done, put the wheel back on and make sure you have no more play.
This is the quick and clean way to do it, if you want to get really dirty and do it correctly you'll need to pull everything apart, regrease everything, repack the bearings and put new seals on. If you want me to explain the whole process just let me know. Good luck with it whatever you do.