I believe you can then grab mpeg's from the HDD with this installed.

You can (ethernet isn't strictly necessary, you could use serial if you're not doing anything for the next few months).. If you're a Windows person then there's a neat GUI that gives you a list of what's on your TiVo and you just hit extract; For Mac/Linux (as of a month or two ago, haven't been keeping up lately) there's more complicated CLI tools or a plugin for TiVoWeb to transfer over HTTP ("save this link as..").