Windows 7 - CPU Upgrade

Hello All,
I have An older HP Pavilian Desktop, with a Intel Core Duo 4500
@ 2.20 Ghz on a Austek Benicz 1.01. Its been running fine but I
would like to upgrade it a little. I would like to improve the CPU
the ram (currently have 3 Gbs) and onboard graphics.
I would like to upgrade the CPU but don't know how to choose
the right CPU. I would also like some help as to what other improvements
I could do. Any help or suggestions will be apriciated.

Thanks

RalphG.

Note: I am running Windows 7.

Model number of the computer would be better. That and the motherboard name you posted isn't quite right as it doesn't come up on a search.

Its a Hp Pavilion a6334f Desktop PC.
The motherboard Asus IPIBL-LB (Benicia) (1 PCI, 2 PCI-E x1, 1 PCI-E x16, 4 DDR2 DIMM, Audio, Video, Gigabit LAN, IEEE-1394).

According to HP,

Motherboard Specifications, IPIBL-LB (Benicia) HP Pavilion a6334f Desktop PC - HP Customer Care (United States - English)

this is what that motherboard supports,

Biggest thing is that it is all socket 775 which has essentially been discontinued and anything still available is for the most part over priced and depending on how you look at it, under performing for what is current hardware (i3, i5 and i7). As for what is available for it, depends on where you look and what the shops/sites still hve in stock. This is what Newegg is showing for socket 775 CPU's,

Newegg.com - Computer Hardware, CPUs / Processors, Processors - Desktops, Intel, LGA 775

Thank you for the reply. I will be looking
into the information you provied.
Let me ask you what do do think of overclocking
instead. I have herd of this but don't know very
much about how to do it. Would you recommend
this ?

Done properly it is fine. One small problem, you have a HP computer and you won't be overclocking at all as HP locks down the bios and there are zero options available for overclocking.

OK Do you have any other suggestions ?
Or should I just be happy with what I have.

Personally or what a new CPU would cost and that it is a deadend socket, I would just leave it until such a time as you buy (or build if so inclined) a new computer.

Thanks for the information.
I think your right.

RalphG