Thanks, I just got back to this. It appears that as this xp computer only has 1 GB of memory and new webpages require more memory to load properly than when this computer was born--certain sites simply take a long time to load on this system. I had noticed from Hamluis' post that i could modify the about:config preferences in Firefox to increase the timeout number. By increasing it from 10 to 20, this problem seems to have been eradicated. I also noted that it only has come up in two sites: Web of trust--which is a useful tool as it identifies garbage sites. However, it was hanging my system so when I got rid of it, half my unresponsive script errors disappeared. The other half were the fault of Optimum webmail's new interface, which takes a year to load on this system. As a result, the loads are way longer than required on other sites. So now that I've increased the timeout in preference, this too seems to no longer be a problem (other than it takes about 30 seconds to load the applet).
Probably I could have also solved the problem if I had bought more memory but as XP is going into hackerland on 4/8/14, this computer is going to be pulled off the internet before that time and sent to pasture, so there's no point investing another $150 in memory to bring it up to the max 2000 GB.
In any case, the timeout fix seems to have worked. The interesting thing is the creeping memory requirements as sites get larger and more data intensive. When this computer first came out, it was top shelf. Now its the Commodore 64 of its day.
It's a shame too because I like XP and would never have needed anything more. . . other than memory enhancements to keep up with the creeping, expanding sizes and complexity of websites. I guess that's why cowboys had a hard time switching from horses to cars.