Windows 2003 Server replication

are they 2003R2?  if so you can use DFS with Namespace for failover

or you are looking at 3rd party software

Failover what exactly?
Seemless for clients?
Version of win 2003 standard or enterprise?
Any additional budget?

I'm using windows 2003 R2.Am running hotel reservation system.data has to be replicated btw the 2 servers ,in case the primary server fails the secondary should kick in or we can manualy change network cables etc ,whatever the procedures are.Clients shouldnt feel that the server is down.

By the way will 2003 standard support the replication or i need to have enterprise.

standard R2 supports DFS but i dont think it is what you are after

nope, DFS wont do anything like this....you are talking about clustering or hot failover software such as netappz tools....you are looking at some big dollars here....

Pls advise on recommended software & procedures to move forward.

any clustering technology should do it, you can even use windows....take a look at this for just one example, i saw this live and was dumbfounded
http://www.netapp.com/products/software/clustered.html