Import title from filename

I must be stupid, I can't figure this out. I have a directory of untagged files. I managed to group-change the album and artist fields, but can't get the title. I want the title tag to be the filename with the trailing .mp3 removed.

How do I do this?

While I'm at it, I've got another directory with the artist name in the file name. How do I tell it to rename all the files but remove the artist. For example
01 - Beatles - I wanna hold your hand
02 - Beatles - Yesterday

I want to remove - Beatles.

Use format with:
FORMAT VALUE: %_filename%

Use regexp replace:
reg exp: ^(\d+)\s+-\s+.+\s+-\s+(.+)$
replace with: $1 - $2

On my fone so hadnt the chance to test.

Use the converter Filename-Tag.
If the filename is the title then enter this mask:
The Preview function in that dialogue should help you to find the right mask
A hint: if there is information in a filename that you do not want then use %dummy% for that part.

The renaming business can be done with the converter tag-filename.
Provided that you have the information in the tags (track, artist, title) then use this mask:
$num(%track%,2) - %title%
(the $num-stuff creates a leading zero)