How do I use ALT codes on a Dell Windows 7 laptop with no numlock key or FN keypad?

Wordpad/Word/Outlook etc. allow also to use Alt-x combination. Enter hex code and immediately after press Alt-x (eg. 41 Alt+x will produce A). Detailed instructions (with much more information) in this Wikipedia article

If you don't have a numeric keyboard to input the desired code, you can use the build-in windows Character Map Utility:

1. Click "Start" menu button;

2. Select: Programs → Accessories → System Tools → Character Map;

3. A window should open with a grid displaying the characters:

   

4. Select the font you're using on your target application;

   ^{Arial works very well across the board and presents all characters. There are exceptions of course.}

5. Scroll the chars grid to locate the desired character;

6. use the button "select" to select it to the copy area;

   

7. Copy the characters when you're done;

8. Past them on you desirable location.

Character Map Utility comes with lots of useful features, take a look at this article that explains all this with greater detail.

There is a subset of characters directly available if you enable AltGr which means changing your keyboard type to International. This changes your Right Alt key into a special kind of shift key, letting you type characters like « and » or letters like á and Þ.