Both methods are not really practicable. The author of tiny Spell seemed to have the same thoughts and decided to create a software that would work as an universal spell checker in Windows using the least amount of resources possible.

Tiny Spell checks all words typed in Windows against an English-American dictionary with more than 110000 words. This is done on the fly and the program plays a sound and changes its icon in the system tray whenever it discovers a word that seems to be spelled wrong.

The clipboard is monitored as well. It is then possible to take a look at the suggestions by either clicking on the icon in the system tray or pressing a hotkey that lists suggestions. The selected word can optionally be automatically copied to the clipboard or pasted into the document of the misspelled word.

Many Windows applications have built-in spell checking but others do not. TinySpell is convenient software available in a free version and you can use it to add spell checking to any application. There is a paid version available with more features, but the free version will suffice for most practical purposes. The Notepad in Windows 7 is a handy tool but does not feature spell checking, for example. If you want to add spell checking to the Notepad or any other application in Windows, this is a great way to do it.
The download link for tinySpell is as follows: tinySpell Homepage

The installation is simple. Just follow the prompts. After tinySpell has been installed, you will find a shortcut icon on the desktop. You can access tinySpell from this desktop icon or from the System Tray Icon. To begin, examine all of the settings to determine if you would like to make any display modifications. Right-click the System Tray Icon. This opens the Context Menu. Select Settings.

Click Add to include all the applications you wish to use tinySpell with. The easiest way to go about this depends on how many applications you want to enable the feature with versus the number of applications you do not want to use with tinySpell. At the top of the window, if Enabled is highlighted, you will be adding applications with which tinySpell will be disabled. If Disabled is highlighted, tinySpell will only be enabled with applications you add to the list.

Add any words to the dictionary whenever you want to. Go to the context menu and select Dictionary.

The spelling of a word can be checked ahead of time by clicking on Open spelling window in the Context Menu. This will open the spell check window. When a misspelled word is typed in, it comes up red.

If you click the check box to the right of the word entry, it will give you a list of correct spelling options. For more complex words, there may be no suggestions. In this case, you will have to add it to the dictionary. Feel free to experiment with it to get a feel for the different possibilities.