Not sure mate – if you put it in the plugins folder as the instructions say, it should come up in the plugin admin menu for you to update. Without it appearing there, you can’t update.
You need to install a plugin, like the Ultimate Tag Warrior. However, the latest version of wordpress (2.3) which is currently being tested and due for release in the coming months, will have inbuilt tag support.
Tags are a new way of organising content – also called Folksonomies. Categories, the traditional way and which is within the core wordpress installation, is also known as a taxonomy.
RSS is supported by wordpress – you don’t need to do anything.
To get your blog noticed
1) Start writing lots of content. Most people get traffic from search engines
2)write lots of recent content. New postings will ping servers, telling them you have written new stuff (that’s partially what RSS does – it will happen automatically).
3) Starting linking. The core to getting traffic, is through links. Start linking to other bloggers about things they say, and you will get noticed.