You should use “All tracks, markers and regions” Auto Ripple mode. That’s it.
If you still want to quickly and easily select the events, then take a look at Select Events tool from Vegasaur extension.
Try to find your-project-name.veg.bak (in the same folder) file. If it exists – rename it to your-project-name2.veg and open in Vegas. Hope this helps.
This problem can easily be done with scripts. You can try to find a free script or use one of the commercial tools, such as Effects tool from Vegasaur toolkit. I believe that other scripting plug-ins also have similar tools.
You can use batch rendering tools with advanced naming capabilities, like Vegasaur Transcoder (it’s not free, but it has free 30 day trial period). It supports various name patterns (aka macros) that control how output files are named. Macros are specially formatted strings that can be used anywhere in the file name for automatic naming of the output files (in particular, pattern {c} will be replaced with the counter value – just what you need).