First of all your three BHO's are all perfectly legitimate;
Smart Popup Stopper
SpyBot Search&Destroy
Related to Sun_Java_software
They keep coming back because you do, or did have these programs on the computer.
Your O16's are also perfectly legitimate, they are all related to SunJava
.
HijackThis should only be used if your browser or computer is still having problems after running Spybot or another Spyware/Hijacker remover or removers
It is NOT a maintenance program.

Interpreting these results can be tricky as there are many legitimate programs that are installed in your operating system in a similar manner that Hijackers get installed. As noted with those above in your post. Therefore you must use extreme caution when having HijackThis fix any problems. I can not stress how important it is to follow the above warning.

Look at all the instructions on numerous websites, including this one READ ME ,for removing spyware/malware/viruses/trojans/hijackers...the final step is using HiJackThis IF other steps have not worked. It should NOT ever be used as part of regular computer maintenance. It is to be used as an AID for cleaning up a computer in trouble, not as a clean up tool.