i am looking for proper OST for these 2 Burnout games if possible...
also Burnout 1 if exists at all...

cheers,
bias.

I don't think Criterion ever released the songs from Burnout 1 and 2 as a soundtrack. The Burnout 1 music is on the main site.

I never heard of official release for the Burnout series.

The only one that is known is "Burnout 3 Takedown OST", that was "EA Trax Digital Release".
edit: i think Burnout Dominator was also release by EA on their store.