Hi i cant connect to internet

Question

hi i got a zyxel nbg334w wireless router ive plugged it in and installed it and it worked for a couple of days then i had to unplug as i was moving computer now it will not let me connect to internet it keeps say limited or no connectivity but if i just use my modem i can get on the net i bought the router so i could use xbox 360 on live the leads go from pc a blue ethernal lead from pc to router then a yello 1 from router to modem then internet lead to modem any ideas y i cant get on?????????