Advice: If you doing it with Sony Vegas then firstly before u take a montage, set the present settings to HD, liko 720p or 1080p (File->Properties). I see from the quality options on youtube that you've done the video on these decent resolutions so far, the thing is that your video is set on 4:3 aspect ratio, if you wanna make it on 16:9 (widescreen, HD and no deformation), just select the the particular clip, press right mouse button and select option "Video Event Pan/Crop" then in appeared window press right mouse button again and hit "Match Output Aspect" (Remind: you need to do this in every clip, 'cos the settings are set for particular clip not not for all on the timeline). If you use Sony Vegas and didn't know it, I hope it'll help you