You will do well with the 3570K.
Make certain that you have updated the bios to support ivy bridge first.
You should be able to just exchange the cpu's, and Windows 7 will take care of everything.
At stock, the heat is not remarkable.
Even with a mild OC to 4.0 or so, heat is not an issue.
It is only when you are pushing high>4.5 OC's that may require upping the voltages that heat will be an issue.
Do not worry about ram speed.
The current Intel cpu's have an excellent integrated ram controller. It is able to keep the cpu fed with data from any speed ram.
The difference in real application performance or FPS between the fastest and slowest ram is on the order of 1-3%.
Synthetic benchmark differences will be impressive, but are largely irrelevant in the real world.
Only if you are seeking record level overclocks should you consider faster ram or better latencies.
Read this Anandtech article on memory scaling:
http://www.anandtech.com/show/4503/sandy-bridge-memory-...