How can you brighten up a dark room? (please read details for more info.)?

I am a tad bit in over my head. I posted in the decorating forum a day ago. But I still need a bit of help. We live in an apartment. Standard white walls (scratched and dinged up by the former owners), beige carpet (yick), white kitchen tile (I could spend all weekend cleaning the floor, but it still looks dirty), pink/tan kitchen counters (double yick) , two windows, and there is a giant tree blocking the window in the living room. Needless to say, the whole apartment is DARK. It is just so depressing. We don't have much on the walls at the moment, but I did buy two bright and colorful paintings. But the place desperately needs a makeover. We have an old, dark brown cloth, hand-me-down couch that we cant afford to get rid of and a recliner to match, (AND my husband doesn't want to get rid of it. It was his grandparent's the couch and recliner set) a couple matching tile end-tables, (that we bought from an estate sale), and a black wrought-iron coffee table with a glass top (that we picked up on trash day. Its actually really nice. Not sure why anyone would toss it.) So, I need ideas to help brighten the place up. I dread going home at night because I hate that no natural light can come in, and when we do turn on a light, it just accentuates how empty the place looks. I need ideas! (I'm new at this. This is our first apartment, and I want to make it look nice.) What colors are in now for window treatments? How can I brighten up this gross kitchen? Cover up the tile? What else can I put on the walls? Lighting ideas? Ways to cover up this gross-a$$ couch and recliner? Just give me any ideas you can. Any other apartment dwellers feel my pain? Thanks! Much appreciated.