Whilst the port to VB6 will be pretty painless, you should be aware that MS
ceased support for this language earlier this year. As such, it does not
have future as far as MS are concerned, although many will continue to
develop in it and OS's will support it until that after Vista, apparently.
Also, many are unsure as to how serious MS are about VB.Net as a long term
If you are starting from scratch, then why not look at the whole range
available to you, as long as it COM support, so you can interact with Excel.
Just my 2c.