Microsoft Word Doent is opening as SQUARES ?

I have quite a few archived MS Word files covering several years and I can no longer open them, they just appear as all Squares when opened. I've been looking around in internet for answer. Opening these files in Wordpad it's the same, there is of course nothing in notepad as this is a text editor.. Opening file with Word 97 it's the same. I did not save these files to flash drive before hard disk, as some suggest is the problem. What I can think is different is they were created in windows 95 operating system before windows XP was installed. So I guess it might be a font problem. I did not use Strange fonts, usually the default times roman or ariel is what i use. So how to find out which font is needed to be around, so i can reload it and resave it to correct it? Or is it corrupt beyond recovery? I use MS word 2000 on windows xp. Thanks in advance for help with this.