I am planning to buy a laptop and setup a wireless network in my house. My desktop has XP as its OS, but the laptop will likely be a VISTA OS. Will I be asking for trouble or are these OS's similar enough to work together? I have heard all OS's must be the same. True or false?
While I can't speak for MAC vs PC, I can say that various (Windows) PCs can interact and play nicely with each other.
I currently have a XP Pro SP3 regularly exchanging files and printing with an XP Home SP3; I also periodically exchange files between the XP machines and a Win 95 machine; and when my kids visit files and printing can (are) exchanged with Vista SP1 machines.
From a personal standpoint, I know that XP and Vista are similar enough to play nicely together, both in networking and as far as sharing the internet. (In fact, in my home we have one XP desktop, two XP laptops, one Vista desktop, and one desktop betatesting the newest Windows system... never had a problem.) And from a technical standpoint, pretty much all Windows systems have been designed to do just that: play nice together. (In fact, the newer Mac systems are starting to work the same way.)
Congratulations on the new laptop, and hope everything works out well for you!