Question About Installing Windows 7 On Two Computers

I'm getting a copy of Windows 7 64 Bit to install on a laptop,and i was wondering if i can use the same serial code to install it on my desktop as well. I know that i "can" do it, what i mean to say is will i have to worry about Microsoft seeing two separate computers using the same serial number during some update, or verification check, and not allow me to use it anymore?

Yes.  Essentially all Window NT based OSes are individually serialised even if you use the same key.  The key determines the license alone.

Legally, no.  Can you?  I don't really think so.  When installing Windows, it'll make a record of what your hardware is and once activated is tied to that hardware.  I can't remember the number of times you get for reinstallation but after a certain point you'll have to call in to get an activation instead of being able to activate it online.
 
Short answer:  No.