Unity is a tad slower, but not any slower than GNOME Shell. It is similar
to my KDE. If it is significantly slower, I would check that you allowed
enough SWAP and your free memory situation. You should also check your
graphics driver which can slow things down since Unity uses compositing (as
does GNOME Shell). Unity 2D is the same but does not use Compiz. You can
try running it and if it is faster look to your graphics driver and see if
you can get a better one.

Oneiric allows you to drag and drop icons from the Dash to the Launcher and
to rearrange them. To get an application click on the Dash and type the
first few letters, thu for Thunderbird for example. That should start
bringing the icons up as choices to launch. You can launch then by clicking
or can click and hold and then drag and drop then to the Launcher. This
will give you a customized Launcher. You can later rearrange the Launcher
so your most important icons are at the top.

If you do not know the name of the application a part of it will usually
do. You can also use the Filter by clicking on More applications and a
filter will appear at the left. When you click on Graphics filter it will
present you with the graphics only applications. Click on display more to
see all of the icons.

Unity is different but very usable. There are shortcuts. You can use the
Super (Windows) key to get Dash to open. Ctrl-Alt-T brings up a terminal in
a hurry. Alt-Tab switches between running applications.

For more see:

www.ubuntugeek.com/...nity-keyboard-shortcuts.html

https://help.ubuntu.com/community/KeyboardShortcuts

It may seem like a bit of a pain at first, but I am excited by the
challenge using something new. Good luck on troubleshooting your
speed issues.