Ubuntu – Can I Use Ubuntu Server As A Desktop

an older relative of mine still has Windows XP. The hardware is ok for XP, but definetively too weak for Windows 7. Also, I think, Ubuntu would be a nice OS for him to work with, since it's easy and has a great feel.

HARDWARE
The machine has 1 processor with one core (3 GHz) [Intel(R) Pentium(R) 4 CPU 3.00GHz], 1,5 GB RAM, 80 GB HDD. But it has some weird VGA-Chip [VIA/S3G UniChrome Pro IGP]

PROBLEM
I installed Ubuntu 12.04, Lubuntu 13.04, Xubuntu 13.10 and even Linux Mint: I simply cannot get a desktop. All the installations run without problems, but I keep getting stuck with The system is running in low-graphics mode. I tried all the answers to this problem (since there is a good thread concerning this error here), but I think, the VGA-Chip simply doesn't do it (someone wrote "Unity requires: Any graphics card with OpenGL 1.4 support"). I spent two days, trying to get to a desktop, I couldn't succeed.

SOLUTION?
Out of curiosity, I installed Ubuntu 8, which worked fine. Of course, I couldn't update it. Then, by accident, I installed Ubuntu Server 10 (instead of Ubuntu Desktop 10). After the installation, I installed a desktop (sudo apt-get install ubuntu-desktop). Then, I updated to Ubuntu Server 12.04, still with desktop. Everything works fine. I have an Ubuntu LTS with a working desktop.

QUESTION
Is there any serious reason, why I shouldn't run a Ubuntu Server as a Desktop?

The guy, I'm doing this for, just wants:
– open office or libre office
– internet browser (firefox would be good)
– thunderbird
– skype (yeah, it's Microsoft… but some of his relatives are outside the country and using skype)
– software for viewing and collecting photos
– to use a HP laserprinter, a standard-webcam (for skype) and card-reader
Everything shouldn't be a problem, as far as I see it.

If there IS a problem with running a Server OS as a Desktop: Is there any other way to install Ubuntu Desktop and tell the OS not to use any kind of desktop-features, that need newer VGA-cards (kind of like the windows 2000 theme)?

Yeah, I could make him buy a new pc, but I just hate to waste. This guy doesn't want to play the newest games, cut videos or render 3D-graphics. He just needs some office-programs and internet-access.

What do you think?

Regards,