Importing a MKV with multiple audio tracks, and a MKV with subtitles, into iTunes

[Silvestris]

Hi, I'm able to import MKVs into my iTunes by opening them with quicktime using Perian, and then doing "save as movie," which makes it a MP4.

However, one of my MKVs has multiple audio tracks. Does anyone know to convert the MKV into something that would work for iTunes while being able to keep the other audio tracks?

Also, another MKV has subtitles. The subtitles aren't burned into the MKV, however there's no way to remove them when the video is in quicktime, so I'm unable to save a subtitle-less MP4.

Can anyone help me with either of the cases?