J.G.
since you mentioned a R. squiggly, I'm guessing you're talking about Word. I'm looking at Word 2010, so it might not be exactly right (I'm guessing you're using Word 2007 if you using Vista). First, make sure you type a few misspelled words. If there are tabs at the top, go to the "review" tab. Click on Spelling & Grammer. When the box pops up, click on "options." Another box will pop up, and on the bottom half will be a box you can select that says, "Check spelling as you type." If that is selected, it should now give you R. squigglies for those misspelled words.
Good luck!