If you don't have a firewire port on the PC you will need one to capture from you MiniDV camcorder. What about USB ports. Better to have USB2 for analogue video transfer. I wanted both and only had a single PCI slot free. I found this http://www.dabs.com/uk/productView.htm?quicklinx=2J0R which has worked a treat. Has both USB2 and firewire ports on the same card for under £19.

As for the resolution question. I wouldn't worry about it. It's not the capture box that's at fault, it's the original source. It's simply the case (unless anyone proves me wrong) that the original VHS tape is already at that 300(ish) by 200(ish) resolution. Analogue video is low res, which is why the capture res for these devices is quoted lower than you hopes to see.

My route for this job is to capture from my A-D device. This gives me a very large AVI file at low res, of the order of 1Gb per 5 minutes of footage. This is imported into Adobe Premiere for editting. The export (encoding) from here is where the resolution change occurs ready for me to burn to DVD. The resulting display when watching the final DVD is as good an image as I had on the original VHS copy. Certainly, from memory, I'm seing no degradation in quality.