DetlevD, thank you too for quick and detailed help.
I decided to use use this variant, with replacing characters, because of
1. remaining double quotes in cell,
2. not soluted, too, tabs in field,
and because it meets booth my needs,
3. backup and
4. quick search in spreadsheet, without loading all files into Mp3tag.
Excel 2003 spreadsheet cell able to store 32,760 (I think, 2-digits - because I use unicode) characters. And as I found on the net, txt-format (what I need for restoring - Excel>txt>Mp3tag) has no line lenght limit.
Have a nice week end!