The living room, den, office and dining room are probably the spaces where you spend the most time. Sitting on the sofa in front of the TV, reading, playing with your kids, eating meals, paying bills. While a lot of the basic cleaning tips will get most of these rooms clean, there are a few things that need special consideration.
Let's start with the clutter. This is where it lives, more than anywhere else. So before you even start cleaning, go through your book, DVD and CD collections and weed them out. Why clean something that you don't really want? Electronics also tend to be kept in these places, and do they ever get dirty. You don't want to clean electronics with anything wet, so dry-dusting is your best bet. It might also be worth buying a lint-free or non-static cloth to get rid of any dust or smudges on the screen. Your computer may be full of dust, so consider opening it up (if you're into that kind of thing) and spray it out with some canned air. This is the best way to get dirt out of the keyboard too. Got that tangle of cords behind your entertainment center or desk? Sort through and label them all, or even buy a system to bundle and organize them.
Fireplaces are beautiful, although these days they aren't used as much to keep your house warm. They can also be a mess. If you used yours in the winter, it needs to be cleaned. You can handle sweeping or vacuuming out the ashes and debris, as well as wiping down the stonework or brick with an all-purpose cleaner. Getting rid of build-up inside the fireplace is best left to the professionals. Spring is the best time to do it, so it'll be all ready for next winter.
I always mean to file papers weekly. Or monthly, at least. But I don't. Even if you're really diligent about maintaining your file cabinet, you may want to go through and throw out anything really old (with so much stuff online, you probably don't need your power bill stubs from five years ago anyway). If you can't ever find anything, it's time to reorganize and make a system that works for you, whatever that may be. While you're in the office, clean off your computer or computers of any old files and make sure you're backing up everything you want to keep, whether that's by an external hard drive, a server or an online service.