Sqlservr.exe reaching high mem usage in task manager, and sql database not responding

First let me quickly say that after years of knowing about experts exchange i have finally decided to purchase support, my first question was answered in 20 minutes.  This next issue has been a constant stress on our company operations and I'm hoping to get some answers. I want to thank in advance anyone helping on this matter.

We are running a windows 2000 server machine with 2gb of ram.  It's sole purpose is to serve an sql database version 7.0 that is used by 2 other computers that share the same local network.  We have a windows nt server machine running as an IVR.  The IVR is using a third party application that can succesfully send queries to the sql server and retrieve field values.  When the IVR and SQL server are started the memory usage  on the SQL server is at around 800mb, this value slowly climbs as the IVR receives phone calls and the sql database is written to.  The value caps at 1,821,872 K Mem usage and further queries from the IVR result in success for the most part but are sometimes not returned properly by the sql server.  This results in error codes in our third party app with no description.  We are constantly waiting for calls to hangup and then restarting the SQL server on the win 2k server machine to "reset" its memory at 800mb and restore the performance.  All commands to close recordset and db objects are being invoked by the third party app on every query it performs.

We have thought that it was the size of the db that was the issue as it was over 2.6gb, we then decreased this size to 1.3gb but yet the memory usage still would climb to 1,821,872 on the win 2k server machine and we would experience the same intermittent results from sql at memory cap on the server.

The second computer accessing the sql server(which we have removed from this equation entirely and still experienced the same climb to memory cap), is a windows 2000 terminal machine that has an access 2002-2003 file format.  This access db has links to the sql tables and also has visual basic code behind form buttons that access sql directly, updating, writing and querying data to output into access listbox's and other form objects.  The activity of this database also increases the sql memory usage on the win 2k sql server machine, but as I stated we have removed this from the equation yet the memory still climbs just from the IVR NT machine querying the server(though nowhere near as fast).  The use of this access db is integral to our business and yes all of the visual basic code is closing recordset and db objects. rs.close db.close.  


1)Is it normal for SQL to reach memory cap as it is queryed?
2)Is there anything i can do in access to limit the memory usage of the sql server?
3)Any advice or help would be greatly appreciated, thank you.