I personally would not put things in the documents & settings folder.
I would create a folder right off the c:\ location.
At a previous place of employment, we created C:\BAK\2k2 and c:\bak\2k4
for the different versions.
I would do something similar to this for your AutoSaves, BAK's, temp files etc.
create a folder called C:\AutoCad then make different folders for the different options.
Then you can set your search paths to the different folders. This may seem overkill but
it will help you keep things organized and to know exactly where to look for certain files.
You could then create some type of program to clean these folders out every 2 weeks of whatever your heart desires.
The startup lisp is just a lisp routine that gets called each and everytime AutoCad is started. This would either be located in the acad.mnl (prior to 2k6 & 2k7). Other names would be acad{version}doc.lsp
There are infinite ways to have a startup lisp. it all depends on what you have in your office.
100MBS for LAN speed is as good as it's gonna get unles you have a gigabit office. This would be 1000MBS. Have your IT people check on their end as there maybe lots of collisions of data thus slowing things down. it also makes a difference if this are auto-negotiating or if they are set at a certain speed. Auto-negotiating **sometimes** will slow things down if collisions start happening alot.
Just out of curiosity what version and what's the average size of your files? Sometimes if you are working with large files, nothing will help the read/write speed
Pieter
