I have ripped a dvd and now the audio is not syncing up with the video. The ripper I use is WinxDVD ripper. My question is, what is the best way to go about fixing the audio sync problem? The problem I have is the audio is ahead of the video. The video format is wmv.

May be ask in a forum dedicated to video? And who uses WMV these days? MP4 has been ruling the video world since the new millenium.

I would try this.
Find out the delay length (VLC), rip the audio track from the video and cut from the beginning (Audacity), and re-encode the video to MP4. (VirtualDub & MP4 codec)

If you intend to watch it only on PC, try VLC and the sync hotkeys.

What's this got to do with Gimp?

Go to a video forum for help in these things. I know many ways to fix your issue, but won't do it here. Besides it's very boring to fix audio sync issues.

I've used MP4 before and I hate it. I use WMV format because it seems that it's the only format that my laptops (I've had more than one) can handle.

You're using WMV which is likely using "Variable Frame Rate" which is likely creating your audio sync issues. Stop using wmv.....