Fogot my encryption code

I had a wireless network set up for me about a year ago and now would like to buy a new laptop. I do not remember my encryption code. It is a D Link router. I wrote it down somewhere and will likely find it after the problem is solved.
What is my best plan? The guy that did the network is no longer in the area.
IF I reset the router, I understand that it would erase the code. Can I set up another encrytion code afterwards? Is there some way I can get the code now from the three computers already attached? OR finally, I am planning on having my old lap top hard drive data transferred to the new computer, would the code transfer as well?

Networking is something totally GREEK to me so please keep replies at Grade 1 level...Thanks.

 

you should be able to reset the router, and then be able to go into the router control panel and setup a new password....it won't automatically do that for the other computer(s) on the network, but they should recognize the network and ask you to enter the password...

 

That is great to hear. Hopefully it is as easy as it sounds. Thanks very much.

 

Yes, you can run this http://nirsoft.net/utils/wireless_key.html
on any PC already on the network, rather than blowin out the router and starting over, especially if your not that 'geeky'.