Need Suggestions/Advice

One of my clients has a Check-cashing store(Plus they give Payday/small loans ---- hope you experts know about the biz nature). My client and other store owners are thinking of starting their franchise by merging about 10-locations(All locations are in the same state). They are thinking of having a centralized database(either Oracle or SQL-Server or any recommended) with web as the interface.

Kind of information that they usually pull:

1. CustomerScreen: Shows customer's information + his/hers picture --- We havent decided whether picture would be stored as a BLOB or they'll be stored in a shared-network drive

2. TransactionScreen: Shows customer's transaction history + Check-Issuer's transaction history(ie. history of checks we've cashed by the issuer)

3. Each location on avg. has 3-computers

What kind of network connectivity do you recommend?

1. T1s (Dedicated or Shared)
2. T3s (Dedicated or Shared)
3. DSL

I'm looking for a cost-effective solution. But at the same time it has to be FAST as currently every store's information is stored locally on their drive.

Also, please suggest OS:

1. WinXP
2. Win2K
3. WinNT

thanks