Before moving on, let's talk hardware. The sad truth is that not every device will work with Linux. You should not think of this as being strange or as somehow representing a weakness in Linux. After all, Linux is not unique in this. In fact, Linux may be fairly unique when it comes to the sheer number of devices and platforms that it does support. Linux runs on Intel-based systems as well as Alpha, RISC, and Macintosh systems. IBM's entire line of computers, from small desktop PCs to such large mainframe systems as the S/390, run Linux. Then there are MIPS, SPARC, and StrongARM. You can also find Linux embedded in microchips, running on portable MP3 players, PDAs, cell phones, and even digital watches. That's incredible hardware support!
From the perspective of your computer, it is highly unlikely that Linux won't install and run well. If something is going to be unsupported, it will have to do with some Windows-only modems, printers, or scanners. To find out whether or not your computer and its associated devices will work with your Linux installation, first check your Linux vendor's web site. Another great hardware resource is the Hardware HOWTO. You can always find the latest version by surfing on over to the LDP's Linux Hardware Compatibility HOWTO page at http://www.tldp.org/HOWTO/Hardware-HOWTO.
As Linux gains in popularity, you'll find that hardware vendors are increasingly interested in tapping into this ever-growing market. I remember being on site, adding hardware to a customer's system (Ethernet cards come immediately to mind) and finding that the system did not have the drivers. When I quickly visited the Ethernet card manufacturer's web site, I found precompiled drivers ready and waiting for me. With the incredible growth of Linux, it won't be long before these issues are a thing of the past.