I have lost a lot of my PC Gamer demo CDs over the years, and it looks like the Interstate 76 CD is one of them
And I've never been able to find a site on the Internet, even PC Gamer's site, that lists anything about their past demo CD's or their contents. Somewhat surprising, but maybe I'm just not looking hard enough.
As for
Blood Bowl, that game is from like 1995, and Interstate 76 came out when I was 12...so 1997. I really have no idea what this game is, but I doubt Bloodbowl.