Since all the data stored on the dvd is in mpeg2 format, you will essentially be calibrating the computers dvd player. Now it may be that this will get you close to perfect... or it may be that it makes it worse.
You should really use a freeware tool like Nokia monitor test. Search for it online. it's free and very reliable.
I don't think so. Avia and DVE are for calibrating to watch movies in their best conditions. I'm not sure it'll be good for websurfing and other computer related tasks. It'll probably end up setting it way too dark.