What you need to do when starting to use Opera is to create your own contextmenus, toolbars, buttons, mousegestures, searches, hotkeys etc. The people over at the Opera forums are a great resource and there are plenty of pages that help a lot, like
this for example.
Here is a picture of my context menues, although they are changed a bit now. (Programs/Favorites have real items now, I have also added "Open this page in IE" / "- FF" submenu) The first five is when I right click on a normal page, the sixth is RC on a link and the last one is LC on text.
There is also a similar one when RC on pictures.
Adding custom searches can also save you a lot of time and armmovement. By going to the adressbar (F8) and typing "g overclocking", it will do a google search for overclocking. By pressing SHIFT+CTRL when I press ENTER, the page will open in a new background tab, so you don't even need to CTRL-N a new tab to do a fast search. I have added [i=imdb] [w=wikipedia] [d=dictionary] [ig=google image] [gg=google "I'm feeling lucky"] [p=piratebay] [t=torrentspy] and a few more that I have forgotten.
Im also about to make a "piratesearch" that launches 4-5 torrentsearches at once.
You can have up to three functions on a single button (plus you can give it a dropdown menu) and have it do basicly anything you want from starting a list of sites in the background to have Counterstrike connect to your favorite server, or the server whos IP you have marked.
You could also read
this. Its rather old, but I think it covers the Opera basics.
This is my Opera, free for buttons since I only use hotkeys and contextmenus.(7.21 skin on 7.54 Opera)