Recommendation for returning to a Mac?

My last five primary computers...

Power Mac G4/400, OS X 10.2.8
Gateway Celeron M laptop (ML6230), Vista Home Basic
Dell GX260 P4 1.8 desktop, XP Home
eMachines EL1200 Athlon single core desktop, XP Home
Acer Extensa 5230E laptop, T4300, Windows 7 Home Premium

The Acer is currently being used as my desktop. I like it. I'm happy with it. I would still rather have a Mac. My IIsi antique machine isn't going to cut it.

I have a dual core processor and don't want to go backwards. If I'm going to buy a Mac of some kind to use as a desktop machine, I want it to work with perephirals I already have. All I want to buy is the box. Be it a newer Mini or a somewhat used G5 Tower. My display has VGA and DVI ports. My speakers, webcam, keyboard, and mouse are Logitech and all USB-powered.

I have looked through Low End Mac and see that some of the older G5 towers can be had in the $300-$500 range. In fact, one place has 2.3 Dual models (supposedly the most reliable) for about $550. $450 with damaged cases. But these will run Tiger or Leopard, not Snow Leopard. I couldn't tell you the difference since the last Mac OS I had was Jaguar and that was on older machines (G4/400 and the G3/300 I had before it).

Or should I simply get a Mini? I wonder if a Mini, even a 1.83GHz C2D model, would be a step back from where I am now with the 2.1GHz Pentium Dual Core in the laptop. I'm sure the graphics in a Mini are better than the 4500MHD on-board. But is it comparable and will it work with all my Logitech stuff and a VGA or DVI display cable?

It also looks like about $580 will buy a new Mini with nVidia graphics and a 2.26GHz Core 2 Duo. That has the display adapters I need (miniDVI to DVI or to VGA) and Snow Leopard. 2GB memory, 160GB HD. Same specs I have now as far as that goes.

It's either one of these or I'm building another PC from an Athlon II X4 630 processor, Windows 7, and an ATI HD4670 video card for around $600. I already got my wife a $1200 Core i7 box. She couldn't be happier although I think a 24" 2.8GHz iMac would have been more fun for the same amount of money.

From everything I have read, the Pentium Dual Core in some of todays notebooks is no where near as good a CPU as a C2D. I was just helping a friend who wanted a Dell Notebook and there was the Celeron, then Pentium Dual Core and then the C2d. The C2D was the highest priced of the dells we were looking at. I only see that Pentium Dual Core in the lower end models.

The main thing that suffers with that Pentium Vs C2D is lower Cache which can sometimes make quite a difference depending on what you are doing.
Also the Pentium is running an 800 Bus compared to the faster available on the C2D.

http://forums.cnet.com.au/laptops/core-2-duo-vs-pentium-dual-core-10006416t.htm