I don't Think much of DOT NET however it is a better idea than Using VB runtime files in this sense,If you get what i mean.
VB.NET is not alot of fun all be it, it can do some smarter Visual things than Visual Basic 6.
Generally cuts out hours of coding for Window GUI's that was required in Visual Basic 6
Ya its a whole new lang to learn.
Linux programming seems rough as crap to me however you'll be sure that some kid will tell you different.
I think The learning crub is very steep for Linux however it would pay off once it this crub is reached.
Also On Linux alot of things are left unsaid all be it someone will point you to doc's here and there and tell you to read somthing at TPL.org or some place which is totally usless for anyone but an under-ahceiver or kid ,ie. if you ask a question this happens as 90% of you support for the system is people that have no idea what they are talking about,just like I talk now.
Win$oft you have msdn.microsoft.com Linux you have stuff spattered all accross the internet for particular interfaces,distributions, and libs.
There is no General Glossary in which you could gain a Picture of an Unkown Subject in 4 hours