1. Yes, but only on minimum settings due to the lack of a separate graphics card and the age of the integrated graphics
2. Not important, it's a feature that was made standard on everything a very long time ago.
3/4. Complicated. It would be 2 at 1.73GHz, can't combine them, BUT the GHz number doesn't equal performance, and a modern single 1.73GHz CPU would actually be faster than a single Pentium 4 3GHz. You'd need to look up benchmarks to tell depending on game. The second CPU allows it to run some things in parallel if the game supports it but it doesn't add to the first.
Can you tell me the name of your integrated graphics chip? From "Name" on Display tab of dxdiag. Or better yet your laptop model number so I can check myself.







