1. In the command line, you must change to the directory where a file is present to execute it(or give its full path). In your case, you have to move to the Desktop which should be something like
Of course, replace 'user' with the username of your account. Then if you run the nvidia installer, it should work.
2. Most linux applications have lowercase executable names. i.e 'SuperTux' could actually be 'supertux'.
3.The command for changing screensize etc. is definitely not "Screen Size & Rotate".
Try running the command "mcc", choose hardware->ScrenSize..... etc. when it crashes, there must be an error message, that'd would give a clue as to why it is crashing.
Also you can try [ctrl]+[alt]+[F1], this gives you a command line(actually stops the x server). now you can login as root and try the command "xorgcfg".
I think the error message would have been more like "Bad Exit Status"
6.I have no idea what you are talking about, maybe somebody else would be able to help you better on that. Sorry.
7. As far as i know, it'd not be possible to 'upgrade' between two different platforms. Even if you did, it'd be the same as a fresh install, all the 32bit packages would be removed.
8. Do you mean it didnt work yesterday and that it works today? Even linuxquestions uses php so if you face any problems elsewhere and not here, you can most probably rule out a problem on your side.
9. It is very difficult to say, each has its pros and cons and it depends on what you
I'll post a couple of links, I havent read them(just googled them), but i suspect they'll be distorted and finally ask you to decide(that's the thing with most reviews).
10. try running 'limewire' in the command line, it could also be listed in the menu, under internet and filesharing.
11. LE 2005 is pretty able as far as partition detection goes. Find the folders listed under the folder "/mnt". Also you could try to add it to your desktop by Right-clicking->Create new link to device.
I hope i have answered most of your questions