I have windows 7 Pro, and openoffice is unstable here too. (Crashes 5 times a day, every second time i use it)
I think it is just amateur software, as the length of the document goes bigger it crashes more often.
Try to open one (or more) of Andrew Pitonyak's ODF type Bacro Book documents. They have hundreds of pages, pictures, Styles, and they works fine on our PC-s even was installed Win7 x64 Pro, or Win10 x64 Pro on it. (Because they are large, but WELL STRUCTURED documents)
https://www.pitonyak.org/oo.php/How large your documents are? What a file type are you using?
If the Macro Book crashes too, then check your hardware. Maybe something is wrong in it.
If the Macro Book not crache, then check the structure of your document: the file type, the styles and the manual formatting properties, the installed and the used Fonts... etc... Maybe something is wrong in it.
Never use foreign, never standardized file formats, like the old, obsolete, binary MS-Office file formats (.doc, .xls).