First things first.. For an initial attempt without guiding, its not bad.. you can clearly see that its M42, thats definitely a start!!
You might want to spend a bit of time drift aligning your mount.. I've managed to get mine good enough to run 4 minute unguided exposures with very nice round stars.. Guiding is generally seen as a requirement for good images.. even the big boys with over $100,000 worth of scope/mount/camera guide... this is because more than just the polar alignment affect how a resulting image will look..
PM me if you would like a copy of the easiest drift align method i've found on the net.. its very very easy to follow and it will definitely improve your imaging capabilities...
Cheers mate, Good going
Alex.