You need to convert the NSF files to PST format then you can view the PST files without Lotus Notes, these PST files can be opened with MS Outlook tool that comes as free of cost with MS Office package.
To convert NSF to PST, please use Export Notes tool from:
http://www.systoolsgroup.com/export-notes.html
At the conversion machine you need to have Lotus Notes & Outlook installed at the conversion time, these may be trial editions, you can get them from respective websites as well.
Let me know, if you face any issues. I will further guide you back.