Windows 7 Professional x64 Internet Problem

Two weeks ago I finally got rid of Vista and installed Windows 7 professional x64. It has been working fine until yesterday when suddenly this problem with internet came up.

When I started my PC at first internet worked but the ms was HUGE. It seemed like when I started my PC our whole network started to lagg which scared me. After a while I tried to reboot the modem and the router to see if the the lagg could be gone but instead my computer started to act wierd.

When I started it up again it like always connected to both the network and internet. At first both internet, msn, ventrilo, world of warcraft was "working" good (still with high ms) but then all suddenly internet and ventrilo stopped working while World of warcraft and like 1 out of 3 MSN conversations still worked :S
After a while thou everything died. So basicly internet is up for around 5-20 minutes depending on what program it is.

When I tried to browse internet with firefox or explorer it never even responded to my adresses I typed. I just was blank and said in the corner "done". This meaning that it didn't say "cannot find www.randomsite.com" or anything which I find really wierd. In the first few minutes it worked just fine with any webbrowser.

When I check my status on the connection it says:

IPv4 says "internet"
IPv6 says "No internet Access"

I am atm at work and can't share any values or anything from my compuer (yet), thou I will if needed when I come home


Notes:
*I am using a wire to my router (DGL-4300) by D-link
*Note that I am REALLY the biggest retard of computers and network, so please respond in some kind of way that I can actually understand.
*It has been working fine just until yesteday and I haven't installed any new programs the day before.
*I've tried to update Windows 7 as much as I can.
*I've disabled everything that I can think of blocking internet such as firewall etc.
*Other family members using Vista or XP got their internet running fine until I connect, then suddenly the lagg comes.

However I am very thankful to those who takes time to try to solve this for me.
And I am also sorry for my bad english.

/Rikard

Hi Gary!

System restore was one of the first things I tried. Restored it back 2 days first, then another 2 days since that didn't help. Still no effect :/

Sorry for not telling you in the thread and thanks for reply.

Rikard