When my cats had a flea outbreak the vet first gave me ProMeris (which didn't do much good). Then I tried Revolution and it has been working great. As for the fleas in the house, my vet told me "vacuum, vacuum, vacuum"...and empty it out when you're done each time so the fleas don't crawl back out. I also bought a flea-killing spray for the carpets and furniture, just make sure your pets don't get on the treated areas until it's dried (I just closed them off in an area and did one room at a time, then switched as it dried).
Don't get frustrated (I thought it was the end of the world!
) Just keep up with the meds on the cat and keep vacuuming and spraying and they'll all die soon enough.