Yes, you could go buy a wireless modem router etc, BUT if you then have problems and Talk to Orange \ Wanadoo they will blame your Wireless modem router.I am with Orange \ Wanadoo and have a Linksys Wireless modem router, works fine.
I beleive that there is a new standard comming out ADSL 2 (possibly ADSL +2) don't know that much about it, I think its for faster connection, but if the exchanges are not up to spped, a bit pointless, but if you are looking at getting Wireless modem router, might be worth seing how much a ADSL 2 costs.
Personally, I would save the money and Hassle Orange \ Wanadoo.
Steve