What version of Lion do I have?
It looks like a developer preview of Lion Server was installed at one point overtop your current consumer version of Lion. You can't do that.

I can't (under penalty of compromising my confidentiality agreement with Apple) go into detail but installation of Developer seeds are not so simple as to keep installing new versions. There is a process to ensure nothing breaks.

I assume your brother is not a registered developer and was not made privy to these processes, hence the errors above.

In short, your system is hosed. I would recommend reinstallation from either the MAS or using the Recovery HD (boot holding ALT ). It's of note that reinstallation of Lion will not remove the contents of the user profile and aside from having to download the OS, quite painless. Simply boot using the Recovery HD, select the location of the installation (your case, Macintosh HD) and sit back. Once done, you will have a fresh copy of 10.7. Then you can use Software Update to install 10.7.2 (and any other updates you require).

Then give your brother a good wallop for (allegedly) pirating OS X (and another for his ineptitude and pirating the wrong flavour)!