DOSBox is freeware!
It doesn't work on Win 98. You don't need it for Win 98 because Win 98 has a native DOS mode. The whole idea was to create a DOS environment for operating systems that don't have any, or have poor, DOS support. These are:
Windows 2000 and XP
And to answer your last question... all you need is DOSBox. It only takes 10 minutes to install and configure. For instance, here are my set-up instructions for Under a Killing Moon:
1. Download and install DOSBox
version 0.62 (or later). Get the Win32 installer version, which at the time of writing was called:
2. Wherever you installed DOSBox to, go there and edit the file dosbox.conf, replacing the section at the very bottom of the file with the following (Note: if your CD-ROM drive is letter 'E', then replace the 'D:' below with 'E:'):
# Lines in this section will be run at startup.
mount D D:\ -t cdrom -usecd 0 -ioctl
mount C C:\
Another note: you have to get that exactly right, so it's best just to copy and paste right out of this web page and into the dosbox.conf file using Notepad or a text editor. While you're in that file, you should also set: fullscreen=true (it's set to false by default) and cycles=13908. Note: you may have to experiment with the number of instruction cycles DOSBox emulates every millisecond, depending on the speed of your processor. I arrived at this figure by using multiples of 9272 (the setting which was recommend for DOSBox 0.60). I have a 2GHZ Pentium IV. Generally, the higher you can set this value to the better. You'll know you've set it too high though if the sound begins to stutter!
3. Open a Command Prompt (Start -> All Programs -> Accessories -> Command Prompt) and Install Under a Killing Moon to its default folder, C:\MOON
4. Manually copy the file: TEX197.EXE from the CD to the C:\MOON folder.
5. And now we're ready to roll! In a Command Prompt, switch to the folder where you installed DOSBox (for instance: cd \Program Files\DOSBox-0.62). Start up DOSBox by entering:
Then enter the following 2 commands after it starts up:
...and we're away!
6. The very first time you start the game, you are taken directly to the sound setup page. It's best to set up the sound manually. Use the following settings for the DIGITAL SOUND DEVICE:
SoundBlaster Pro, I/O Port: 220, Interrupt: 7, DMA Channel: 1
Accept the defaults for the MIDI MUSIC DEVICE: SoundBlaster, I/O Port: 388.
7. When it comes time to set up the screen and so forth, try setting the Window Size to: 640 x 480, and the Rendering Quality to: HIGH. If the in-game motion turns out to be not fluid enough for you, then you can set these parameters to lower values later.
So, what are you waiting for? I'm willing to help anyone who is having trouble getting a particular game running!
And one other thing. It's also a perfect tool for slowing down games that run too fast. Just keep reducing the 'cycles=' parameter until the game becomes playable