Laptop requirements are minimal. XP, Win7 or Win8, 32-Bit or 64-Bit all work fine. I would have at least 2 GB of RAM and 50 Gb of free hard drive space.
Any eBay seller of ENET Cable should work, or get an ENET Adapter like this:
Ethernet to OBD2 Adapter (ENET)
http://www.one-stop-electronics.com/...&product_id=23
Since F25 uses mostly the same ECU as F10 (e.g. CAS, FRM, CIC/NBT, etc.), you can use F10 Cheat sheet, and most codes will work the same.
I do not know what you mean by "bulb warning".