Welcome to the forum.
You might want to take a look at this ARTICLE. It starts with a checklist of things to do, to get PrE working smoothly. Next, it goes into tuning up the system and OS, and finally has links on troubleshooting problems.
In particular please let us know what model of camcorder your video is coming from and what format it is.
Version 3 of the program was very limited in terms of the types of video it was able to work with.
Also, indicate how much free, clean, freshly defragmented space is on your C drive. An XP computer is at least 6 years old, so it's probably full of tmp files and fragmentation.
Of a forum in our country, I got the tip. Remove Elements 3, Control Panel Software. As well as in the register In the register, I saw nothing in front of Premiere. Then install Elements with a disabled virus scanner. Fortunately I can use Elements. Thanks for your answers.
The same problem suddenly made my Premiere Elements 3 unusable yesterday. I got the same message -- "A serious error has occurred..." - whether I loaded a recent project file, an old project file, or tried to create a completely new one.
After reading through this thread, I tried freeing up more disk space, running file and registry cleanups, repairing the software, and finally reinstalling the software. None of these actions fixed the problem.
Another Google search came up with the following article about fixing the same problem in Premiere Elements 7:
I figured it was worth trying on Version 3. Even though the software re-installation must have created a new Styles folder, step 2 in the article fixed the problem. It involves simply changing the name of the Styles folder (My Documents/Adobe/Premiere Elements/3.0) and letting Premiere Elements re-create it. I kept the first program execution clean and simple by just having it create a new project. After that, I could open my big project files without any errors.
Hope this helps anyone else who runs into this problem