Conditional Value List On The Web

What I am trying to do is have a conditional value list on my sites search page.

Each client logs in, then when they access the search page they get a value list in the site field showing each site we do work at. The problem is the speed. the database has about 110,000 records and it takes 2-4 minutes to load the search page because each time it needs to gather the value list.

I have got this working two different ways.

1) Showing all records from a field in the value list but having the privileage set limited to displaying records that relate to the login name.

2) Working the same as the above but having the value list looking at another table that has about 250 records.

Both these are do what is needed but take far too much time. Anyone have an idea on how I can speed this up?

All fields are indexed and the only calculation in the who database is the one used to limit access to the records.