1. & 3.
Dumping the combo VCR was a wise move. Those VCRs tend to give lousy image quality, and are usually build with shoddy workmanship and plastic parts. Those decks quite often eat VCR tapes, because they're just thrown-together in quality, and have lousy transports.
Using XP mode is a smart move, too. You don't want to use SP mode (lots of compression) --- unless forced (due to poor recording compliance by the XP mode, which causes known-good media to pause/skip/etc on DVD players.) You never want to use anything longer than 4 hours, and even then most DVD recorders are lousy beyond 2 hours.
Which DVD recorder are you using?
VHS-C tapes tend to be quite lousy. The tape format is not very well engineered, and transport problems were common. That would result in hard-to-play recordings, especially if not using SP mode. The tapes were also very easy to "eat" by a VCR, when put into an adapter. For that matter, I've seen tapes eaten by known-good VHS-C and S-VHS-C cameras!
The only adapter recommended by this site is the metal/battery JVC C-P7U, which was included with higher-end S-VHS-C video cameras in the late 1990s and early 2000s. It is very well made. Of course, that's only part of your problem. You also need a good VCR.
Actually, you need several VCRs. The JVC-SR-V10U is not really like the other JVC S-VHS VCRs, not identical, at lest. It can play SP mode VHS-C tapes quite well, and it won't eat the tapes. For any tape that gives you issues, you'll need a Panasonic AG-1980P. That is complicated, however. The 1980 often plays tapes with magnetic dropouts, or "comets", in the image. You'll have to later filter that with something like
VirtualDub, using methods we've discussed on this site in the past.
And that doesn't even include the other software and hardware you really need (like a TBC), to get good results.
Sweating heavily with a finger on the trigger (stop/eject) is wise. Of course, just realize by the time you hear a problem, it's too late -- you've lost something. And eject won't help much. In fact, it will just make the problem worse, as the ejection of a tape will further damage an "eaten" tape. Have screwdrivers handy, and hopefully your VCR is easy to pull out and dismantle.
Heat is also a contributing factor to VCRs eating tapes, in general.
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2.
You really should use a proc amp -- a piece of hardware. By the time video is converted to digital, a lot of the possible color corrections are now impossible. You'll be working with a very diminished signal. To restore video, you must do as much as possible pre-digital capture, while it's still in an analog chain.
Womble makes great "editing" software (cut/splice), but it's lousy at anything that would require re-encoding video, as color correction would do. I would never suggest
Womble software for this task. Wrong tool for the project. Save
MPEG Video Wizard for editing MPEG files (removing footage, removing commercials, etc)
If a proc amp is unavailable, then the best that can be done (working with the degraded available digital video) is to use a higher-quality editor like
Adobe Premiere (preferably the Pro version, not the Elements version).
VirtualDub, using the Color Mill plugin, also has some color correction abilities, though it can be harder to work with, and is not as robust as working inside a full NLE like Premiere.
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Sometimes, for certain projects, it's a better idea to outsource videos to a pro that knows what he/she is doing, is using the right hardware and software, and can demonstrate decent working video knowledge. (Not just somebody that places an ad online or in print.)
For most people, projects like this are a one-time deal, and you don't want to destroy family videos in the process!
