How to add subtitles or words to a video clip on my computer?

I have a video (taken by my husband's iPhone) of a song that a group of us sang for friends at their going away party. I'm copying the video from my computer onto a DVD-RW, but I really want to add the lyrics of the song onto the video, like subtitles or like a Karaoke song. I know how to photoshop images really well, but have no clue how to edit video.

I have a Macbook Pro laptop, (If that matters.) Can I do this with "Garage Band" (a program I already have but have never used)? Is there an iPhone app or program I can use to do this?

Any help would be appreciated! Thank you!

Added (1). My version is "Mac OS X 10.6.8"
The video file format? It's a.MOV
Is that what you meant?

Not sure but I have a friend that might know. I will try to get her to answer, or I will edit later with a better answer.

If you have iMovie, it lets you add subtitles to your videos.

There are a half-dozen ways, depending on your OS version and the video file format.

EDIT:
For soft subtitles that can play on any computer…
-- Install Perian and QuickTime 7, links below.
-- Open the MOV file in QuickTime Player.
-- Go to the Window menu > Show Movie Inspector. Note the frames per second, data rate, and normal size details.
-- Use QuickTime Pro (US$29.95), Prism, or Any Video Converter to convert the MOV file to AVI. Take care with the converter AVI settings to match the FPS, data rate, and normal size details.
-- Write your subtitles in TextEdit, but at Save, change the file name to end with.srt, and the name to match the movie (For "Kid Birthday Party.mov", the subtitle file must be "Kid Birthday Party.srt"). For examples of how a subtitle file must be written, search for any popular or classic movie name at http://allsubs.org
-- If it is a popular song, find the lyrics, copy from the lyrics web page, paste into TextEdit, and add the reference numbers and times between the lines, like this…

1
00:00:02, 100 --> 00:00:05, 100
Bye, bye, Miss American Pie

2
00:00:05, 200 --> 00:00:08, 100
Drove my Chevy to the levee
But the levee was dry

Play it to see how much you need to adjust it. If it doesn't play, it is because…
-- You made some mistake in the format of the text, such as wrong time (00:00:02, 100 means 2.1 seconds from the start; 00:01:02, 100 would be one minute 2.1 seconds-- 00:00:01, 35 won't work correctly, but 00:00:01, 357 will) or wrong spacing (pay attention to each space between --> stuff and each blank line in your sample you got from allsubs.org).
-- The two files are not named the same. ("Kid Birthday Party.srt" is different from "KidBirthday Party.srt")
-- The two files are not in the same folder.
-- QuickTime is not set to play subtitles (menu bar > QuickTime Player 7 > Preferences > General > Show subtitles when available.

Another option; this is how to make a DVD that can play in a DVD player on top of your TV or in a computer that has DVD playing software…
-- If your computer is not 2011 or later model, it came with iDVD (which happens to be discontinued now). Use it.iMovie is the app that came with your Mac for editing movies. Then it has an option to Export to iDVD, which has a Help menu, and if that doesn't answer all your questions, use support.apple.com for "iDVD menus" or whatever your question is about. You can add subtitles in iMovie or in iDVD.

-- If your 2011 or later computer came with no iDVD, use DVDStyler. It is a free (not a demo / trial) open-source alternative to iDVD for Intel Macs. It has most of the same options as iDVD, but not as many cool themes.

For a ten minute video, I would suggest soft subtitles, since they can play on any computer (Mac OS systems need QuickTime Player 7 and Perian or VLC Player (very poor quality, but many geeks love it) to play movie files with soft subtitles).