Advice on Upgrade

In 2004 for home desk top PC purchased a Dell XPS, PentiumR 4 CPU, 3.40 GHz, 3.39 GHx 2.0 GB RAM.  At the time, that was considered high end.  Over time have upgraded some components, 120 GB on board HD, 1TB Seagate external drive, dual CD-RW and DVD+ RW. 

Still running MS W-XP.

Use computer to surf internet, watch movies (HBOgo), so gaming, and primarily run numerous business applications based on MS Office Pro.

I'm on my 3rd laptop since then for travel and probably my 4th at-work desk top but feel it's beyond time I upgraded my at-home PC.

Have read C-NET and PC World reviews of ODE systems and I'm impressed but not sure which way to go.  Was attracted to processor speeds (I don't think humans should ever have to wait on computers) for multi-tasking and overall high quality, but concerned I don't need some hardware (dual video cards for example).

I don't want to say $ is no object, but 7 years ago spent in excess of $2300 on the XPS which was a lot of $ at that time.  I went on the theory that I would buy the most computer I could afford at the time to have the best chance of a long service life.  I think I did alright on that go-round.

Using the same theory now, is a high-end gaming system my best bet for functionality over time (even though I'm not a big gamer) or am I barking up the wrong power cord?  If so, suggestions for a different direction would be appreciated.  Thanks.

If you are not a big gamer, then the ode 1 is more then what you need, but keep in mind, unlike dell and xps pcs, we shop our pcs here cause if anything goes wrong we can just go to the store near us and change the part, vs having to use dell psu or mobo and etc.

you can also easily add parts to these pcs.

when it comes to performance lasting a long time, first thing you want is the most powerful cpu you can get, after that its really up in the air, if you don't game at all I'm sure a single 570 will be more then you would ever need but if you throw games in the mix now that becomes different, to keep pc great in gaming, depending on how heavy of gamer you are, its best to upgrade gpu/s every 2 to 3 years.