Usually there are no issues when opening Word documents in OpenOffice (OO) or saving them back out as a .doc. To save an OO document as a MS Office Word document (.doc) go to File, Save As and select Microsoft Word 97/200Xp doc. (2007 and 2010 home users take note: .docx files cause issues)
When editing an intricately formatted MS Office document in Open Office, it is important to save the working copy as an OO document. Often, new users will open a .doc (Word file), format it in OO and then save it back out as a .doc. This may effectively undo all of the formatting changes that were just made in Open Office. The process of opening a .doc in OO, converting the .doc to an .odt (OO format for a word processor document), making the changes in OO and then saving it back out as an MS Document "re-converts" the OO formatting back to the MS version - which are often different.
So....if you are editing a document made in MS Word, open it in Open Office and save in ODF format. This will make a new copy (not overwrite your original) and maintain the formatting. If you need to get OpenOffice for home use, use this link and download a copy, it works on Windows, Mac and Linux.
If you are still having issues with documents, contact the Professional Development Center in your building, they are happy to help convert your documents.