is there a straightforward guide? I cant understand how to use dosbox at all in the way of opening a game....

did you read the pinned topics at the top of this section? they have pretty clear instructions.

i cant get anything to work in dosbox

Can you get DosBox, itself, to run? What do you enter after its windows pop up? Where do you have Arena installed?

i dont understnad the coding in dosbox inthe example.....what it does.
arena is installe here: D:\Games\Arena\ARENA

After starting DosBox, ignore the DOSBox status window and just use the one with the Z: prompt.

Try typing in the following:

mount c c:\games
c:
cd arena
arena

All things being equal, which they never are, arena should start. If you want to play full screen instead of the small window, enter alt-enter. To get the mouse to work, you may need to enter ctrl-F10

All of this is described much better and more thoroughly in the sticky at the top of this forum.

Or, better yet, check out http://www.gamesas.com/bgsforums/index.php?showtopic=848878 and Sephiroth's most excellent front end. The download is under his signature and all you'll have to do is download and install his program, copy or move your arena folder to his System folder, and select TES: Arena as the game to play.

Okay, type these lines to play the game.

MOUNT C D:\GAMES\ARENA
C:
CD ARENA
CORE DYNAMIC
CYCLES 15000
ARENA

You could try higher values for the cycles, such as 20000 if you want. The higher the number, the faster the game will run, but it will also require a faster processor. You can also change the amount of cycles while you play the game by pressing CTRL+F11 and CTRL+F12.

(Freddo is right ... I made a mistake in suggesting "mount c c:\games ... he picked up on the correct drive for your install (D))