If your home Pc has retail version of Office 2003 then you can install a
second copy on your laptop. However, if the Office on your home PC came
supplied by computer maker like DELL or HP then the only way to get
additional license is to buy another copy of Office 2003 from AMAZON.
If this the case then you should buy the latest version (Office 2007)
which can be installed on your home PC and laptop.
The best thing is to buy the laptop and try installing the Office on it
using your CDs. Then try activating it online and if it fails, you will
be given a freephone number to ring MS. Just ring them up and explain
to them calmly without using any abusive or aggressive language. You
never know it might just work.!!