I installed Netlimiter on the kids comp to try to corral their bandwidth usage, it worked to a point but it didn't really solve the hogging problem and once they got a PS3 it didn't work at all cause you can't cap a PS3 from any computer, nor from the game console. Once we started to get IPhones and a IPad the lag just got worse and got to the point that I just couldn't be on the internet while they were on their devices.
I replaced my old linksys with a new Netgear R6300 router, asked some questions on how to use address reservations and QoS came home and set it all up and was the best thing I did cause I have my sanity back along with little to no lag any more when the family is on their devices and best of all being able to corral the PS3's bandwidth usage.
The R6300 is a bit pricey but it comes with a media server in it inwhich I didn't know until not that long ago the full potential of streaming video so you can watch movies through the PS3 into your tv, and I needed my old dinosaur linksys router to be replaced anyway.
If your going to get a new router then research them out get one thats QoS, 5G supported and a media server built in is a added bonus if your tired of having the family huddle around the comp monitor to watch movies.
My wifes IPhone4 contract is up late next year and its upgrade is imminent. Apple to upgrade to '5G WiFi' this year? ? The Register