Can I suggest that you don't do this? If you want to display the books in calibre like this, add an custom column that builds the "series title" from the other columns. You can then change the displayed columns to show this title, rather then the standard title.
The advantage of doing it this way is that the basic metadata is consistent with the metadata sources and you can use the metadata source plugins to maintain the data without any extra editing. And if you change your mind about how you want to show the title, you can. Also, it is common to want the title like this on ereaders. Most don't handle the series info, so a metadata plugboard is used to change the title in the copy sent to the device.
If you want to do what I suggest, then you can create a "Column built from other columns" with the template:
Code:
{series}{series_index:0>2s| - | - }{title}
As to regex to create when adding the book, I can't think of how to do it. I suspect the simplest way to it is to set the title and series from the file name and then run a search and replace across new books in a batch.