If an online solution will work, take a look at Google Drive (formerly known as Google Docs). It can do word processing, spreadsheets, presentations, etc... and can be accessed from your Windows 7 PC or Asus tablet.
I'm not aware of any word processing software that runs on both Windows and Android but there are lots of packages out there that can produce files that are read/write compatible with each other. For instance, there is the free Open Source LibreOffice which can run on your Win 7 computer and reads/writes MS Word compatible files. Likewise, on the Android side, there is the free KingSoft office package that can read/write Word compatible files.