Vista upgrade of Vista Full Version?

Is there any difference between the 2? I am looking to get this and trying to find out if there's any differences.

Well upgrade is just that, an upgrade. Meaning you need to have an existing XP to qualify. Full install means no requirement for any OS.

Upgrade doesn't mean you need to install XP first though, just have a qualifying XP CD to insert and prove that you have it already. That would basically be any full install XP CD, and no restore CDs like Dell, HP, etc. give.

I understand that. I just want to know if there's any difference between Upgrade and Full versions (software and/or applications wise). I plan on getting Vista Ultimate but if there's no difference between Upgrade and Full, other than needing to have a previous version of windows to use the upgrade that would save me some money.

And on that note if I do get the Upgrade version. Will it install from the XP upgrade version?

That is the only difference.

Upgrading from an upgrade probably won't work. If you currently have XP installed, and boot from Vista it might allow it. I know it worked for XP Upgrade. You will have problems if you need to install fresh though (as in if you bought a new HD).