If you are on a very tight budget, then this should do it at least. It is an entry-level processor compared to most of today's newest systems, but its still going to give you a noticeable bump in performance over your previous single-core processor. The combo uses an ASUS board, at least, which is good as I prefer their brand above any others out there. Good DDR2 memory, though only 2 GB, it can be upgraded later for only $60 or so to 4 GB of memory.
One thing to consider, if you are reusing parts from your existing previous computer, is your power supply. What is the brand, and what is the power rating on it? Power supplies tend to lose their capacity to output at their max rated power over time, and if it was just enough to run your previous computer, it might not be enough now after 4 years to run your new computer build thus requiring a new PSU as well.
There are a lot of ways to go out there to save some money in situations like this. If you are looking for kits or just hardware parts instead of a complete computer, I would suggest looking into AMD systems (which you currently seem to be pursuing) or look into the slightly older generation of Intel processors, such as the Core2Quads as some places may be selling these systems pretty cheap to get them out of inventory and update their inventory to the latest i3/i5/i7 systems.
When it comes to the entry-level and budget build systems, no matter what you might be told, AMD is the way to go. Getting an entry-level Intel system means several hundreds of dollars more than almost the same performance on an AMD system. Just as an example, I recently built an i5-650 based Intel dual-core computer, and while it was pretty sweet performance for the money, I could have purchased an AMD Phenom II X4 955 quad-core system for less!
