1. Yes, print "<$_"; prints a perfectly good path.
This stumps me then. Although I'm not up on the tr// operator...what happens if you comment that out and try "safe" names (such as "aaa")?

2. I don't care for security so far, all I want to understand is why when I enter ,say, myfile.html in a form, it UNDERSTANDS it, spits it out at the print ">$_"; line, and seems to behave PERFECTLY WELL ..EXCEPT when it gets to the open file line.
Well, I'm sure KM has already given you a security rant. I'll just add that it's easier to include security from the start than it is to rewrite. That said, I understand your concerns about understanding what is going on.

Let us know what kind of warnings it generates.

Averall I like Perl very much. Reminds me a lot of C (my favorite language of all time.)
Soon you will love perl more. (near) Equal power, much easier to program. C will always have it's place though (gotta write the perl interpreter in something :))