I went to Tahiti and Bora Bora a couple of years ago but not from Dubai. We went from LA to Papeete with Air Tahiti and then from Papeete to Bora Bora with Air Tahiti Nui (which does all the flights within Tahiti to the different groups of islands).
All up we spent about 6-7 weeks there, and we travelled around alot of the islands (seeing friends, diving, property hunting)...From memory the Air Tahiti flight was about $16-1800 US, can't really remember as I didn't pay for it. One thing I would suggest if you do go to Bora Bora is to get a travel pass for the Tuamotus which allowed us to go to Huahine (in our opinon MUCH nicer than Bora Bora), Rangiroa, Tikihau and Fakarava. There are also other air passes to go to different chains of islands but I can't remember too much about the details.
With regards to time of year - just be careful of August - from memory that is the "peak" of dengue in Tahiti. Both my OH and I caught it in Fakarava. Well somewhere around but it was in Fakarava where we got sick. That said the weather is GORGEOUS and the diving fantastic....
Just be aware that the local currency (pacific franc; XPF) are WORTHLESS outside of Tahiti so try not to take too many away with you :)
If you want to know anything else just ask - OH travels to FP frequently and has an office there....
For Example you could fly by Emirates A 380 from Dubai via Sydney (approx. 14 hours) to Auckland (2-3hours) and then from there to Bora Bora via Air New Zealand/Air Tahiti (approx 5 hours) or
Ethiad from Abu Dhabi to Sydney and with Virgin Pacifi to Rarotonga for example. Virgin is partner of Etihad.
www.virginholidays.co.uk/brochures/worldwide/holidays/south_pacific/tahiti_and_bora_bora/
www.airtahitinui.com.au/specials/tahitivacationspecials.asp
http://getaway.ninemsn.com.au/fspacific/frenchpolynesia/18017/bora-bora-nui-resort-spa
June to Oct should be the "dryer" time to travel there
<em>edited by Domi on 18/01/2011</em>