Which version do you have at the moment Jose?
I have Ver 9 and it will definitely open files as far back as Ver 5. I can't say whether it will open Ver 4 files as I missed that version out so don't have any Version 4 files. I have some Ver 3 files that I discovered on a disk recently and these won't open in Ver 9. My answer would be to open and save it in stages up to the verison you have. In other words find someone who has Version 4 (for example)that might open Version 2 and then save as 4, open these in 5 or 6 and save as 5 or 6, open in 7 or 8 and then save. The font names will have definitely changed since version 2 so you will have to update the fonts used.
Hope this helps,
Joe