windows command line: can I tell Service pack number?

systeminfo | findstr /B /C:"OS Name" /C:"OS Version"

Source: Find windows version from command prompt

You can get it using WMIC - wmic os get servicepackmajorversion

For more on using WMIC, see this little tutorial: http://quux.wiki.zoho.com/WMIC-Snippets.html

You can type in CMD:

Winver