@AlexanderKamp If you just want to save the websites you have open, the easiest way is to export your bookmarks. Go to Menu, Bookmarks, then Export bookmarks and save the file. You can import that file into another browser.
If the browser keeps crashing, you can also copy your Opera profile folder to be safe. On Windows it is usually under AppData Roaming Opera Software. Close Opera first, then copy that folder.
Tell the technician that Opera is crashing and you need help backing up your open tabs and profile before uninstalling.