I have a 2 story home with all wood floors and big oriental rugs. I went through more vacuums than I can count. Nothing really picked up the dog hair and dust on the wood floor though.
Then I started doing research and came up with Miele. It is a lightweight (7lb) canister vacuum that can suck the eyes off a cat (joking, but it is REALLY powerful). It is a LIFESAVER. For one thing, it will stay going even as you have it tipped backwards and carrying up stairs. Is has a bag that seals off completely, so germs never spread when you change it. It has a super long telescoping handle so I can vacuum the ceiling fans! It has a SEVEN YEAR warranty. I have mine cleaned every 2 years. Comes with the attachments as well!
I got a Carina (yellow). I think I paid $399 and got 2 boxes of bags with it for free. Here it is on Amazon: http://www.amazon.com/Miele-Carina-Canister-Vacuum-Cleane...
I have had Dyson, Eureka, Hoover, and something else . . . Can't remember the name. OH! Kenmore! NOthing (and I mean NOTHING) came close to this sucker!