If I want to access unix box via VPN tunnel,from windows box.

What sould I configure on the windows client PC, and what should I enable on the Unix Server box ?

I am using Solaris V10 intel platform, and I am using windows XP, and 2003 for client

On solaris side, have openssh or ssh running.

On windows side, you need a softwar like putty ( type putty in google)

start pytty, fill in the host, protocol ssh,
now from the tree on left side, click on tunnels, and add new forwarded port

eg. Source port:127.0.0.0:4502
Destination:sol.ip.add.rss:port
145.78.220.15:3389

Click on connect >> enter the login name on solaris >> enter password..

You have a tunnel setup now.

But I'll also suggest that, if you just want to make a secure connection to solaris box, always use SSH protocol to connect and for file transfers use scp tools eg. winscp

Hope this helps.