About Wii and regions.
NTSC and PAL refer to the scan lines on your TV. Anything that connects to your TV will have to match the same scan line format.
North America = NTSC
China = PAL
World scan line map.
Region locks are often referring to something different.
DVDs and most consoles that play disks have a region lock. This is to ensure that Americans play games sold in America and Chinese play games sold in China. This is because pirating is much more common in China and merchandise is much cheaper there too. Without the region lock Americans would buy media directly from China instead of through middle man and piracy rates would go up.
China sells everything. If your mom is careful I imagine she can get something with the proper scan lines and region lock. Just make sure it is designed for Americans and not locals.