I have given it a lot of thought, and the answer is: it depends. Was all human life eradicated in one event that made everyone drop dead where they were standing, leaving rotting corpses littering population centers? Or was it a slower process, and people died in the privacy of their own homes?
The best-case scenario, for me, would be a massive event that happens at 3am, and turns everyone into little piles of compost, so that me and the dogs could move to the Mall, and not have to deal with rotting death.
Benefits: A food court full of industrial sized refrigerators and freezers, and (hopefully) stocked with food, a generator, a movie theater, a bookstore I could use as a personal library, a Disney Store all to myself, and all the clothes and Frangos a girl could need...although I'd probably spend the first few weeks breaking into David's Bridal so I could wear fantastic wedding gowns as I forage for shelter and learn how to disarm emergency alarms.
Downside: I'd have to learn optometry since I already wear glasses, and my prescription is getting worse. I'd end up like Burgess Meredith in The Twilight Zone
Any other downsides? Tell me in the comments!