I will explain this for next time. You usually do not need to re-install Ubuntu
to fix a problem. However, if you do, then you can usually restore it if you
copy your entire home directory to another media, such as a usb key and then
copy the files back when you are finished. To do this you need to enable show
Hidden Files in Nautilus, so that you get your settings. To do that press Ctrl-H
in Nautilus and you should see your hidden folders which all begin with a dot.
If you do this, then you keep your bookmarks and address book, etc.

I am assuming that you have a wireless connection since you would not be having
a problem if it was wired. I am not sure if it was set up and worked after the
installation and then quit or it did not work after the re-installation at all.

The Linux way is not to make it harder than the Windows way, but it is the way
it is to give the user control. Everything in Linux is about security or
control, so you will find that it does not do things the Windows way which is
the opposite. Ease of use is sacrificed. For example, it does not log you onto
the computer automatically or start your wireless network. I only point this out
to show that what you see as an inconvenience would generally shock a Linux user
if it was otherwise. Basically Linux people don't want their computer doing
things without their permission and if it does they get annoyed.

If your wireless is setup and working it will show as a connection in the
network manager, in the system tray. It scans for wireless networks and will
connect when you tell it to. Ubuntu assumes that you want roaming mode so that
you can connect to multiple networks, ie. the laptop is moved around instead of
in one place. If you want only one connection then you want managed mode. By
default the network manager icon will be in your system tray and it scans for
networks from which you can choose the one to connect to.

Linux is about control and you can make it do anything, even if it is not made
to work that way. There are ways to logon automatically or to get your internet
to connect automatically. You do this with the full knowledge that it is not the
way Linux was designed to work.

For automatic wireless connection you need to edit a file as root with a text
editor. To get a text editor to work as root you need to open a terminal and
type: sudo gedit, then it will prompt you for your password. The file that you
need to open is /etc/network/
interfaces. I have not tried this as I prefer to do it manually.

see: https://help.ubuntu.com/community/WifiDocs/WiFiHowTo

BTW, it isn't that Linux cannot do it the Windows way. Most distros prefer to do
it the Linux way, but there are Linux distros that work just like Windows. My
eeePC came with Xandros and it connects to the internet automatically, logs you
on without a password and even loads Synaptic without a password. I hate it and
won't use it because it is so lax in its security. There is a tradeoff that must
be made. Maximum usability means lower security. Linux distros are trying to
find a balance that works for everybody and it isn't easy because Linux users
and Windows users approach things radically differently. This is probably the
greatest challenge for Linux distros, how to harmonize two different interests
and ways of doing things.

My personal opinion is that I hope Linux does not try to become a Windows clone.