RPC-1 or RPC-2 means your drive is locked or not (if it says "YOUR DRIVE HAS NO REGION PROTECTION", then it is region-free)... RPC-1.
With some firmware, a region must be set before you can use it. "Setting" a region simply means that your drive has a region setting (as detected by Drive Info) set as the current setting - it does not mean that the drive needs to be "locked" to a certain setting (ie. you can still have a number of user changes left). Most RPC-2 DVD-ROM drives comes with a region changing/setting utility.
While not directly DVD ripping related this is certainly an issue that many people are interested in. In order to manufacture a DVD drive one has to obtain a license from the DVD CCA (Copy Control Association). The licensing terms state that every drive must support certain mechanisms, among others CSS (Content Scrambling System) and region code. The latter has only become mandatory for DVD-ROM drives starting from the first of January 2000. Since then every DVD-ROM must contain hardware region code which the user can change 5 times, then send back to the manufacturer which can reset that counter 4 times. Before that date most drives did not have any region protection and it was rather easy to circumvent the software DVD player based region code protection by the use of a well know tool: DVD Genie. That region free state was also called as RPC-1. A none codefree DVD-ROM is called RPC-2.
Pioneer and Matsushita (they make drives for the Creative PC DVD kits) were the first to introduce DVD-ROM hardware region code protection. But after a while nice people found a way to circumvent this region protection. They argued that they'd been cheated when they bought a protected drive since it's nowhere written down that the drive comes crippled and can't play all DVD discs, and they were quite right. In fact it would be really interested to see what would happen if somebody sued the DVD CCA for violating WTO trade agreements - after all region codes are there to restrict global trade.
The solution to get your drive region free is to load another firmware which disables the region code protection. While loading a new firmware isn't the most uncritical of tasks it can be performed without problems if you take all the necessary precautions. However you should be aware that in some cases the warranty might become void if you mess around with your drive on your own.
If you live in the USA or Canada (R1) then you most likely won't need the ability to play DVDs from other regions, unless you are interested in some of the rare titles that are out in Europe (R2) but not in the USA: For instance the Buffy discs, or the 6 full seasons of Friends If you live in another region than R1 and you don't speak English or prefer to watch the movies in another language then most likely you don't have to flash your firmware either since you get all the titles you want in your own region. But if you prefer to get movies sooner, with more extras, and of course in English all the time then you're in for an upgrade.
If your Dvd is locked i reccomed going to this site it has firmwares for most locked dvd's to make them rpc-1 which is not locked! I did it to my Acer 16/40 which is acualty a pioneer drive! I also did it two days ago for my Dad's new laptop and my friends! the compaq dvd-roms are acutally toshiba locked drives and i changed the firmware back to the rpc-1 toshiba so the drive no longer says compaq in the device manager! you have to make a boot disk though to boot into real dos mode and patch the drive. you can make this from the my computer. right click on the a drive and click format and check the msdos boot disk. Good Luck and remmber you are are your own dont blame me or the site if anything goes wrong yet hopefully nothing will! Firmware Page