My d7 site is in my root and videos work fine. If you are having issues with your videos you need to launch into debugging mode and search through the many many detailed post regarding video solutions. Here are some quick steps to get you on your way
1. Is the uploaded video actually in your flash/modules/video/files directory? No. then you need to track down the problem as the server may not have global permissions set to move uploaded content from temp file to directory; or you may have a file size upload restriction, test again with small file and see what happens.
2. Video is uploaded, do you receive an email from cron after uploading (not immediately but within 10-20 minutes)? No, then cron likely not setup correctly. Do a search for cron and review the many detailed solutions and instructions to run cron properly. Test this by temporarily renaming htaccess in /periodic. Type in browser www.site.com/periodic/cron.php This will force the cron to run, see if you get email and video, if yes your cron was setup bad.
3. Still no cron email, then ensure flash/modules/global/app/ffmpeg.exe has permissions set to 777 (required). Once this occurs, upload another video and test cron as in step 2 and see if files are in directory listed in step 1. Files not in directory, then may have problem with executing .exe, contact server and see if restricted. Files in directory and still not playing, step 4.
4. Is your RMS configured correctly in admin/modules/flash apps? RMS is required to stream the videos to users. If you do not have RMS for server, get one as you cannot serve videos without it.
If all 4 steps are followed and you still have errors, post what Error you are receiving, what step in the process is causing the block. "Videos not working" comment without details of error is useless and nobody can assist you. Be specific and others can help and recommend and remember to use search and follow advice in other post that you think are similar to your issue.