Go to http://www.dosbox.com
Download & Install DOSBox. I recommend installing the desktop shortcut along with the core files, but you can do whatever you like.
Create a folder/directory somewhere on your computer for MS-DOS programs. Call it c:\dos or whatever suits your fancy. (Note: folders and directories are the same thing. Windows calls them folders. MS-DOS calls them directories.)
Go into the DOSBox configuration file (also called DOSBox Options on the Windows Start Menu) and, at the end, add the lines...
mount c c:\dos
c:
...or something like that depending on where your MS-DOS folder is located and what temporary letter you want to give it when DOSBox runs. Note that DOSBox will be pretty much locked to what's inside this directory, so as far as I know, it doesn't really matter what letter you give it. I give it c, which, of course, stands for the c: drive because that's more or less traditional, but like I said, you can give it any letter and put it wherever you want, but for the rest of these instructions, I'm assuming you mounted c to c:\dos
Now, this part's purely optional, but you might also want to put some useful utilities in a subdirectory (for example, c:\dos\uti), and then add this subdirectory to DOSBox's PATH variable with the following command (or something analogous):
set PATH=%PATH%;c:\uti (put this line right after the two preceding lines)
Note that from Window's point of view, the MS-DOS utilities directory is c:\dos\uti, but from MS-DOS's point of view, it's c:\uti
You can put my programs in various other subdirectories under c:\dos. You shouldn't add these other subdirectories to the PATH. Just cd into them whenever you need to. For example, you can unzip Galactic into c:\dos\gal24c
Then, when you run DOSBox, you can cd gal24c and then run Galactic simply by typing gal
I hope this is all pretty self-explanatory, but if you need any help, please email me. Once you get DOSBox installed & configured, it'll open up decades of old software that you can't really access any other way, and some of that you might actually find useful.