Yes, I think it's pretty easy to convert many board games to the tabletop. They generally have to be lower level though; 1:1 level or platoon to a counter (base or stand on the tabletop) to work well.
I have dabbled with using the board game rules Air & Armor from West End Games on the tabletop. There are previous posts on this topic if you search back through.
It works ok, but is right at the upper limit of the scale you can play as you get issues with ground scale and stacking etc. It's a fantastic system though, and I'm working on an article on using it instead as a higher level tactical campaign system for several divisions per side, where the resulting clashes (generally multi-company to brigade level) would be played on the tabletop using other rules.
There are other board games that can also be used as a campaign system to generate lower level battles - eg. GDW's Third World War series, and SPI's Central Front series.
But back to board games that can be (in my opinion) easily converted to the tabletop. Some that I've come across are below. The list is by no means exhaustive, but gives a taste:
- GDW's Test of Battle Series (Team Yankee, Test of Arms, Blood and Thunder, The Sands of War) is really good and at the right level. It even includes a nifty little campaign system for playing linked games in a couple of the modules. Platoon-base level.
- Avalon Hill made some classics that are convertible. Squad Leader and the Advanced Squad Leader series were fantastic games at the 1:1 level (ie. individual Tanks and Squads/Half-squads). ASL is a lot more detailed and subsequently counter-heavy than most rules on the market specifically designed for minis. Also the Panzerblitz series and it's modern AIW version (the Arab Israeli Wars).
- More recently the World at War series by Lock 'n Load Games. From looking at LnL's website it looks like they will soon be re-publishing these. But in the interim, you can download the rules for free from their site if you don't need the counters and boards. Also platoon-base level.
- I recently picked up the re-released version of the classic 80s board game, MBT by GMT games. It is pretty chart heavy and detailed but great if you are into that kind of thing, and the production value is superb. Like the WaW series above, the rules are available for free download from the GMT Games website if you just want to see what they are like and potentially try them for the tabletop. 1:1 level.
The main things you need to tweak to play board games on the tabletop are pretty much common:
- convert the 2D map boards to a 3D tabletop representation
- use miniatures in lieu of the unit counters. Status counters from the board game (eg. 'pinned' etc.) can often still be used on the miniatures table with the minis though.
- convert the hex measurements into inches or centimeters. This is even easier and unnecessary if you play on hex terrain!
- determine whether the board game hex-facing rules are essential to the game mechanics. If not, don't bother with them. If they are, determine a system for how to represent the rules on the tabletop.
- convert the board game hex 'stacking' rules to an equivalent C2 mechanic that replicates the effect (eg. a command radius or spacing requirements).
- determine a way to record and/or remember the information most board games include on the counter itself. This could be replicating the info on the miniatures base via labels, or unit cards or rosters with the info.
Now having said all this, unless you've absolutely fallen in love with some aspect of a set of board game rules (eg. the detail of ASL or MBT), there is not really any compelling reason to use them instead of purpose designed tabletop rules. That's my opinion anyway.
There are simply too many sets of rules specifically designed for tabletop miniatures out at the moment that are good. Often the board games are great for nostalgia value (like the GDW games), but their mechanics were actually overtaken and modernized by their own tabletop rules (like Command Decision and Combined Arms in the case of GDW), or subsequently utilized in more modern tabletop rules on the market today.
Anyway, many board games have some cool aspects. I like collecting them to cherry-pick cool concepts and mechanisms (like the campaign system in the Sands of War) that I can use with my favorite tabletop rules. As a result, a have a bookshelf full of them! Most I have never played, but I enjoy reading them and the nostalgic value they provide...