Download WinZip if you like, but it could be worth trying this first.

I use ME which has a built in "unzipper", and it could be that 98 has too. Double click on a compressed (zipped) folder and it will open in an explorer-type window. Double click on the .exe file in the right hand pane, often called setup or the programme name, and it will install or run depending on what it is. In the case of Hijack This there's only the one file.

Hope that helps clarify things.

There is intelligent life on Earth, but I'm only visiting.