Obama may try to push the issue via any EO he thinks he can get away with.
limitations on what one can due via Executive Order haven't been hashed out, but trying to flaunt a Supreme Court ruling and institute policies that aren't supported by the legislature would trigger intensive backlash from those two branches. Heck, it might be fun to see.
Would he try it? From what I've seen, I wouldn't rule it out. I'd like to say that an actual legislative attempt to pass gun control would find little support in the current Congress, but looking at the vote tally for the original VCCLEA makes me wonder.
Remember that Clinton's second term looked grim. The other guys had control of Congress, and they weren't going to vote for gun control. No way, no how. Or, um, maybe. The lines on that vote were pretty blurry.
Of course, Clinton was better at reaching across the aisle to his opposition, we had a different balance on the Supreme Court, and cultural attitudes were different, but that pendulum can swing back in time.