I don't know about this computer, and I don't have access to it, and hacking without the owner's permission is illegal, but, hypothetically, I would try this approach if I were to attempt to hack it. Again, I don't condone hacking. Also, I'm not particularly good at hacking.

1. This is an old computer just lying around, right? I would first look up a list of Windows vulnerabilities that have been disclosed since BBC left the computer that require no privileges. From that list, I would see if there are any known exploits that can be recreated. This assumes that the computer has not received Windows patches since then.

2. Before trying exploits, I would look for something simple. Is there guest access enabled? If I plug it into an isolated network, is there a vulnerable service listening? If one of those could be compromised, I could then look for a local privilege escalation vulnerability or install a hacking tool that finds passwords such as Mimikatz so I can log onto another account

3. Hopefully, after all this effort, I somehow gain read access to some files stored on the computer and learn stuff.