What do I do as far as security goes?
You definetly don't need to worry about viruses, at least not ATM. You should setup a firewall, but your distribution would probably have already taken care of that (some other Ubuntu users may be able to confirm that).
Do I just install the free anti-virus and firewall programs I got online when I used Windows?
Nope. You won't be needing any anti-virus software at all really. You shouldn't have to install anything for the firewall, unless a GUI for configuration (which Ubuntu probably already has installed).
What will I be using instead of Microsoft Works?
Either OpenOffice.org or
GNOME Office (Abiword, Gnumeric, and GNOME-DB) (less-bloated than OOo, but less-complete).
They should be easy to install from Synaptic.
I don't notice any type of desktop folders such as "My Documents" or "My Music." Do I just create them on my own or what do I do?
Yes, create your own. You have your own home folder (/home/username), and you can use it for any crap you want. Create a "documents" and "music" folder if you like.
how do I change the screen resolution?
Desktop -> Preferences -> Screen Resolution. If the resolution you want isn't listed there, let us know. You'd have to do some messing about.
Thanks for any help.
You're welcome