Hi Aurora
The thread topic looked like "Microsoft windows questions" , with first two words replaced. LOL ,. Anyway.
As for the ad-block plus , there is only the old content blocking that comes inbuilt in Opera .
Spellchecker - i had read somewhere that Opera can take standalone spellcheckers , and use it . I ll find that info and try it and tell you if i get any success.
new features - To tell the truth , i don't remember what is new and what is old .

The browser is so old , that all things are already available in it from versions.IMO. other browsers add it to their newer version after seeing Opera's feature list. Am i right ?
* Most of the old features are improved .
* Changed the default skin , though the old skin is present and can be switched but i love the new one .
* Fraud protection now also has phishing filter added.
* opera link added - same as smart bookmark that was added in firedfox 3 .
* security . performance changes . blah blah ....... blah. you wont be interested in that if i copy paste a changelog . hehe
i don't know , but , is the ad-block so much important ?
ok, i know that answer isn't satisfactory . I ll try to get some more info , but that will need some time.
Nothing is true , Everything is permitted.