Solo Classic and TBC content

Hello :)

my resarch on this has not proven to be enough, so I ask here directly.

Is Solo Raid as a DK possible for Classic and TBC content on patch 3.3.5? If not completely, where is the limitation?

I would like to complete as much of the Reputation, Quest and Raid Achievements on my own. If I remember correctly the Death Knight is the best class for that, right?

Watch Raegwyn Soloing old videos on yt. He even solo some 3.3.5 bosses as dk hybrid.

Ah, forgot about that one. Thanks :)