If you can't afford (or don't want to buy) a retail copy of Windows, I suppose that the best thing to do would be to keep the netbook that you have, and use it as needed. That is, unless you're trading it in on the new one, and if you do, you're probably being shafted, unless it's on it's last legs.
In many cases, you can share the same wireless connection and printer. One thing to keep in mind, once you've learned one OS, it's harder to adapt to a new one with ease. The mind tends to revert to the way things are done in Windows, upon starting to learn another OS.
Check out this article, although you're not converting to Linux, the same principle applies, except that it's not free software in question. But the learning curve is equal.
http://linux.oneandoneis2.org/LNW.htm
This will give you a general idea of what to expect when converting from Windows to another OS.
Best of Luck,
Cat