David has already given us an example to follow (
http://www.dothraki.com/2011/09/any-color-you-like/): Anha vavvirsak haz rhaggat virzetha nakhaan! “I’m going to burn that red cart to the ground!”
Note that the intransitive
virsalat does not serve. With it the burning would be "we", not the city. And the city would fall out of the syntax. Pretty much like if you said "we will die the enemy", "the enemy" would be unsyntactic and strange and "we" would be the ones dying. English allows for most verbs - verbs like "to burn", but not to verbs like "to die" - this funny freedom: when you start a sentence "we will burn...", you cannot yet tell, if "we" is causing or experiencing the burning. That will be determined by how the sentence finishes. Many languages do not allow for such freedom, Dothraki certainly does not. You need to derive a causative from
virsalat, and that is
avvirsalat.
Haz is "that", so for "this" you'll need
jin. That's not for every occasion (there are two words for demonstrative "that" and more for other uses, plus demonstratives inflect when used as independent pronouns), but that's how it works here.
And the idea "to the ground" is indeed evoked with a different expression in Dothraki - which makes sense, as "to the ground" is rather idiomatic in English. A literal translation of David's Dothraki line would be "to the end". That's almost surprisingly blunt and literal!
Kisha vavvirsaki jin vaes nakhaan! is the way to go.
