Perhaps the kitchen is your bete noir? If it is you can do a lot with some new blinds and lampshades. Try some potted plants on the window ledge this can brighten most kitchens. If the paint-work really is past its prime then you need to decide whether you need a whole new paint job or whether you can get away with touching up the doors and base boards. If your bedroom needs a face-lift then try some new bed covers and toning curtains. Add a few cushions to your bed and you immediately have a more luxurious look.
Turn the fireplace mantel into a focal point using color. You can hang different-colored stocking or you can display an array of floral ornaments, also featuring a rainbow of colors. You can even borrow a few ornaments from your Christmas tree and display them on the mantel in a creative way. You can use candles to decorate the mantel and make it glow. Use candles of different shapes and sizes and votives and arrange them as you find it fit. You can also use a few other things in between, like pine cones, Christmas tree branches, tree ornaments, etc.