The MouseHoverTime  and MenuShowDelay  are existing keys, but the others you mentioned for Explorer don't exist (I'm assuming you created them from some reference you read). I changed mine but did not see much of a difference, so I'm thinking a reboot is necessary. I find my desktop tool tips come up in about 0.5 sec, maybe a shade less. Tooltips in Explorer come up even faster, maybe 0.25 sec. That seems quick enough to me for most purposes.
If "0" makes absolutely no difference, it is possible that the value forces a default behavior. Try putting "1" or "10" instead.