Discard PC for Notebook?

Is it worth to discard a PC for a Notebook?
I have a Athlon XP PC right now, and am thinking of upgrading it.
Also, I always wanted to have a Notebook.
Is it possible to invest in a top-edge Notebook (let's say, Acer Ferrari series) and discard the PC?
I use my PC like... 1 week straight on. Can Notebooks take that load?
Also, does notebooks come with optional conections for monitor, keyboard and mouse? Can't find this on specs...
Considering on-board video and audio card... can you play recent games (such as Half-life 2) and use hardcore software (like 3DStudio and Autocad) with no problems?

[]'s

Thanks Mike! I found out lots of things overnight!
Though I'm still not 100% shure on what to do, seems like the best option for me is really buying a Notebook.

I'm first going thru Notebooks specs, then when I have it, I'll pick the Desktop equivalent for comparison.

Just read this nice (and pretty long) technical article that compares AMD Turion 64 with Intel Pentium M (Centrino) processors.
Here: http://www.laptoplogic.com/resources/detail.php?id=17

I'm writing an article on my experience in this... case cenario. Problem is that it's in brazilian portuguese. Anyways, here it is:
http://aoisora.megahospedagem.com. [...] .php?t=700

Next step is finding out how much onboard video and audio affects efficiency. But it seems the answer to that is: Not as much as it did sometime ago.

Also, I'd like to know how good notebook videocards are in comparison to standard Desktop ones. Seems like it's pretty good too... I've seem some benchmark tests on ATI Mobility Radeon X700 (Since I'm leaning towards buying an Accer Ferrari series)... though I still want to know about other options, like the nVidia cards (if there is any of them available on Turion based notebooks)

Anyways, slow but steady, my research goes! XD

Thanks for the help so far!