Well for starters the thin client you mentioned in your post is meant to work with either a Citrix server or a Windows NT or 2000 Terminal Server. The Citrix software runs on both NT and 2000. So the answer to your question about which OS is simple, Windows NT server or Windows 2000 server. Now in order to use Windows 2000 server Terminal Services in application mode, you have to have a terminal services licensing server, which requires active directory. I don't know much about Citrix's current products. If you stick with Win2k Terminal Services, then you will need to get more ram in the server (at least 256megs, becuase active directory is a hog), and I would suggest more storage capacity. Depending on the number of clients connecting to the server you may need another processor. To give you an idea, in early 1997 I worked for a company with 50 users and the citrix server was a dual proc Pentium Pro 200 (1mb L2 Cache), 256 megs of ram and three 4.5gb SCSI harddrives (RAID 5). When all of us would hit it at the same time, it would come to a crawl, especially on calculation intensive excel spreadsheets.
