The joys of excel.... Csv files in excel are notoriously fussy in MS Excel. I haven't really got to the bottom of what setting excel expects and why csv don't jst default to UTF-8 which would mean all character would display just fine. If you want to keep opening in MS excel then Save the file and before opening it you need to right click and open with notepad. Note pad will then give you the option to save as utf8. Then open a blank excel sheet and go to File -> open, find your txt file then a little wizard will pop up, select delimited in step 1, step 2 select comma (semi-colon if that's what you see in the preview).
Alternatively download open office and use there spreadsheet program to open it and it will give you the option to select utf8 and will displa the charachter without effort.