Remote replication question

I'm not a db person so please excuse any simplicity or lack of clarity in my
question.
My company currently uses a model of remote employees updating MS Access dbs
and then transferring those dbs to the main office where they are merged with
a main Access db. The remote employees are disconnected from the company
domain/network during their workday.
The plan is to migrate the Access dbs into SQL 2000 (or 2005?) and then set
up some sort of replication topology that will allow the remote employees to
replicate their daily updates/entries to the SQL Server at the main office.
My questions are:
1) What are the possibilities for the db on the remote machines? Can MS
Access be used on the client side and the Access data replicated to the SQL
server (and if so, would data transformation be necessary?)
2) Can MSDE be used on the remote clients? If so what are the possibilities
for a front end to the client MSDE dbs?
3) How can the replication be done over the internet? I believe VPN and ftp
are possibilities and I think SSL would be a possibility if SQL 2005 is used,
can anyone point me to documentation on how to best setup replication between
the remote clients and the SQL server in the main office.
Thanks
Ideally, MSDE would be used for the sql server replication. In this case you
can't have MSDE publishers of transactional replication, so merge would be
used, with the head office as a publisher and the MSDE databases as
subscribers. This can be best done over a VPN for security. Replication over
the internet is also possible (in SQL 2000 you'd use certificates and TCP/IP
while in SQL Server 2005 you can use HTTPS). For the former option, please
check out this article:
http://www.replicationanswers.com/InternetArticle.asp
Cheers,
Paul Ibison SQL Server MVP, www.replicationanswers.com
(recommended sql server 2000 replication book:
http://www.nwsu.com/0974973602p.html)