The way to limit voting to those who deserve it is to make them work for it.
In my opinion, voting should be limited to those willing to take the time out and actually go and vote. Individual initative should be the deciding factor in casting a vote. Election day comes around only once every two years, and it only takes several minutes, no more than 30, to cast a ballot. Anyone unwilling to get up off of their lazy rearends for a few minutes once every two years should not be allowed to vote. This should also apply to registering to vote as well. Online registration and voting as well as any form of automatic registration (i.e. motor voter laws) should not be allowed.
Voting is a very serious business that should never be taken lightly, the future of our country depends on it.