The � that you see in your CSV file is due to you saving the file in one encoding and reading it in another. Always read/write the files in the correct encoding.
You can decide on a particular encoding (UTF-8 should suffice mostly) and then use the same across all of your text editors, IDEs, Selenium IDE & spreadsheet programs.
You can achieve this by using 'Reopen with encoding' option that is available in most programs.
Solution:
In Selenium IDE options, specify the selected encoding in 'Encoding of test files' field and this should solve your problem.