If it is really Excel 2.0, some later version should be able to read it. I'm not sure, but IIRC, Excel 95 could handle Excel 2.0 files. So: Open Excel 2.0 file in Excel 95, then save as Excel 95 and go on like for any other Excel 95 file.

Update:

I've no MS Office available, but LibreOffice 4.4.2.2 groups Excel files like this in the "Open file" dialog:

• MS Excel 4.x - 5.0 / 95
• MS Excel 97/2000/XP/2003
• MS Excel 2003 XML
• MS Excel 2007 Binary
• MS Excel 2007/2010/2013

So my guess is that are the five latest file formats of excel files. Pre-4.0 Excel files are likely different.

Second Update:

I digged in some old CDROMs, and found two old Excel versions:

Office 97 Professional: Hidden in the custom setup, below "Text Converters" is the "Microsoft Excel Converter" that - according to its description - "converts documents from Microsoft Excel versions 2.x, 3.0, 4.0, 5.0, 95 and 97 to Word 97". Not optimal, but better than nothing. The Excel 97 file open dialog lists MS Excel 4.0 Workbooks as one of the supported formats, and some unspecified "Worksheets". I don't know if that is meant to be Excel before 4.0 or not.

Excel 7.0a for Windows 95: Also starts at Excel 4.0 and has some unspecified worksheets.

So maybe, one needs Excel 4.x or 5.0 to convert Excel 2.0 to newer formats, step by step via Excel 4.x/5.0 and Excel 95/97.

Alexander