Licensing Questions

I'd like to update my licence into the simplest-to-manage and least expensive format possible. 

 

I currently have a fully updated 3-user NIS license serving 3 PCs

running the latest service packs & updates for 32-bit WIN XP-Pro. 

That license has 510 days left on it. 

 

I'm hoping to go out with my wife this week and buy her a new laptop running a 64 bit version of Win7. 

 

What is the simplest & cheapest way to update and manage the licencing for the existing and contemplated new PC's? 

 

Thanks

 

BTW, your reCAPTCHA puzzles are a total PITA. 

I am in the process of trying over a 1/2 dozen times to get this question posted.  

Sound doesn't help; I can't make it out, and can't keep up.