Welcome to our forum and to a great hobby.
I would echo Slippery Squids comments. "Turn left at Orion" is an excellent book. Not only does it list good objects that you can realistically see with a smaller telescope it also gives great detail about the object and is written in an engaging style. Its not just a list of targets and stats!
Hull libraries have a copy. I borrowed it and after a few reads realised it was indispensable so I bought a copy.
Amazon sell this book (price is ~£20 - that seems a lot more than when I bought it 3 years ago - might be worth shopping around). See http://www.amazon.co.uk/gp/product/0521781906/ref=sib_rdr_dp
Its worth looking because you can look at some of the pages of this book at Amazon.
As for the Mars view not sure. If you look at a post in the images part of the forum ...http://www.heras.org.uk/index.php?topic=545.0
... This looks like a good image of Mars but that telescope should give a better results but as Paul notes the seeing was not good so you get a boiled out image. Remember that the images are highly processed and so always look better than with your eye at the scope but you can't beat seeing the object with your eye!
If you can try and join a local astronomical society. They will have someone there who can run through a few checks with you.
Does anybody know of observing societies near Skirlaugh?
An interesting website is...http://www.rocketroberts.com/astro/scopeview.htm
Which simulates images of Saturn through combinations of scopes and eyepieces. I have a 12 inch dob and my view of Saturn even from my garden in Hull was at least as good as the one shown for the 11 inch and 400 mag. I am sure the main gap in the ring is more distinct in mine (Cassini division).
One further point I would try and describe what you have seen via a record. Some people like to write up on a computer and some like traditional paper. It doesn't matter but, particularly if you can do it while observing, you start to look more deeply at an object and see a lot more. It is very rewarding.
Hope you are still enjoying the hobby.