Those are all good measures to prevent producing new space debris. While satellites don't explode very often, it has happened. Upper stages exploding due to residual propellants has happened quite a few times, with the last one that I know about happening last year. That upper stage had been in orbit for many years before it exploded. It was a Russian stage that had been used to launch Glonass satellites in 1990. Here's a good source describing breakups in 2003. More comprehensive info is available here.

This is by no means simply a Russian problem - American, Ariane, and I think Chinese upper stages have all had this problem, too. American upper stages, especially Delta stages, had a bad habit of exploding before measures were taken to dump residual propellants (they evaporate quickly in space). Doing a perigee lowering burn like the one described in the article is a very good idea for lower altitude launches.

Other efforts, such as capturing debris from explosive bolts and despin weights, are underway to cut the production of debris. Preventing explosions of satellites and upper stages would also be a huge benefit, as would making sure the lessons learned from the Long Duration Environmental Facility (LDEF) satellite of the 1980s are incorporated in satellite design.

As for getting rid of debris already in orbit, I read a proposal to use a ground based laser for the job. I don't know if anything has happened with the idea, though.