Fatal counter strike problems

I downloaded steam from the steam website and installed it then installed counter strike. Once counter strike was installed i tried to play and win 98 gave me that blue error screen (press any key to continue). So i pressed a key and the blue screen came up again but after pressing the key again it took me back to windows so i tried to play counter strike again. This time it said HL error then it locked up, so i waited to see if anything would happen and nothing did so i hit restart button and now win 98 is giving me the windows protection error when i try to boot up. I can only use safe mode on that computer now. Anyone have a idea what the problem is?