VPN from win to Linux server: PPTP or OpenVPN or..?

[Joao Clemente <jpcl@rnl.ist.utl.pt>]

I'm searching for a VPN solution to place in a sarge machine I was 
wasked to deploy. This machine must allow a connection from a windows 
laptop to the office network.
Well, the office network has the sarge machine behind a ADSL router, 
therefore I can't use IPSec (AFAIK IPSec needs to be running in the 
public network, there is no way we can portmap from the router to the 
sarge machine since IPSec uses other protocols besides TCP/UDP)

I then turned my attention to openVPN as they state they run the VPN 
over a simple udp port. I'm trying to set up a VPN with it at this 
moment, but I'm having some troubles... while I troubleshoot this, I 
would like to know if someone had experince with PPTP in this cenario... 
Can it be a wiser choice? PPTP at least seems to be standart from the 
microsoft side for ages, while openVPN (in bridge mode - that allows 
samba broadcasts) only works with XP or above...

So, anyone advicing PPTP over OpenVPN? If so, wich server? Poptop?
Thanks
Joao Clemente