Salvador Aguinaga said...

|I've wondered if any of you have used scientific linux on a x86 hardware to
|run a single application ( like an embedded OS ) and disable updates and
|remove unneeded packages?

Sure, at least a dozen times.

|Or if you there is a better alternative to accomplish the same thing.

That depends on what you are trying to do with it.
For instance when I needed a bridging firewall a
few years back, there was no east way to do that
with SL (I tried for 2 day), so I gave up and used
freesco.

But, just for example, we've done this with DMZ
systems, fileservers, and a handful of others.  
Very straightforward; just install what you need,
remove the extras it installed anyway, and only
turn on the minimum services necessary.

Update manually as needed.

Works fine.