Yeah, phpserialize will handle these parameters. Keep in mind that this field is stored as a byte string in the database, so you might have to convert it to a string (using encode()) for phpserialize to parse it.
You can find information about some of the parameters in the
Help:Blocking users manual pages. If the "sitewide" flag is false (0), it's a
partial block and will have additional parameters for the pages and/or namespaces that are blocked. IIRC partial blocks aren't enabled on English Wikipedia yet, so it would only apply if you're working with wikis where it is.
Cheers,
Morten