As for telling if they’re Made in Taiwan or Made in India - please check your packaging.
Booktyping is basically burning the booktype bit in the leadin to say DVD-ROM instead of normal DVD+R/+RW - if you use nero - go to select recorder and hit the advanced thing which should reveal a booktype drop box [if your drive supports it]. Yes, verbs are the best, but your burn looks bad. Please do as we say and post another scan, this time at 4x [select the speed dropdown box] because a scan at 8x isn’t accurate and might not be representative of the disc.
How to tell the powersupply quality - well first of all - check the wattage, and brand. See how much stuff you’ve got in your case. If your motherboard has environment monitor chip - you can use software like MBM, Speedfan, Sandra to find out the voltage readings - and they should be close. If they aren’t, then your powersupply isn’t up to the job. Otherwise, it might be the power supply fluctuates voltage or has noise. Only way to tell these is with a multimeter or an oscilloscope.
Relinking is the temporary process of suspending a burn and restarting it - it happens when data doesn’t flow fast enough to the burner and then it stops for a while. The thing is - if you’ve got a fragmented hard drive or you are working during burning, this might happen. Please defragment regularly and try to leave your system alone if this is the cause of the problem.
As for diagnosing a bad burner, this is harder - try a variety of media, try scanning your burn as we suggested [ but at 4x only] and seeing that the PI is <= 280 and PIF <=4. Some media might not work well with the burner and you can tell by the error rate. Verbatims should be much better. Alternatively, check your cables - try using 80 conductor cable if it’s possible and disconnecting any slave drives if that might cause any issues.