My computer connects to wifi but my browser doesn't work?

[Livason]

I have a computer running windows 7 an I've been having this problem for a while now. I have another computer running windows xp connected to the same network and it works fast and fine. Although my win7 computer is connected to the internet and Skype etc. works but the internet browsers don't work at all I've tried explorer, Firefox and Chrome. This has been happening for a while now, sometimes it works and then drops out. In order for be to be able to use the internet I have to shut down and restart my computer several times. When it does connect youtube videos take forever to load unlike the other winXP computer. Btw my ipad works fine on the same network. Can anyone help thanks
How can I restore it withouth the windows disc

[Cameron]

Wipe you computer clean and install windows 7 all new. Install updates.

[Tom g]

Here this should help fix it>>>

http://windowsfixup.com/2009/04/web-brow...net-fixes/