Can I upload zipped files and all the stuff you can normally do when you add an attachment?
No, I don't think you can do that. From what I can tell, if you want to link images and such to your entries, you'll need to hotlink it from another source with [img][/img] tags (similar to what you have to do if you submit a tutorial to DaniWeb).
Also remember, as Dani pointed out, that a DaniWeb Blog isn't quite the same as something like Blogger where pretty much anything goes. Blogs here should be reporting on IT news (with analysis, opinion or straightforward news reporting) or otherwise be an IT related editorial.
The blogs here are monitored and moderated, and postings which are solicitation, spam, off-topic or otherwise unsuitable do get deleted.
Think less 'personal webspace' and more 'DaniWeb resource'