Update SMF before you trash it,,,,this guarantees the data base will match the new one!!!!
Do a backup of the old sites data base!!!! you will need it for the new system and as a reference..
However since SMF wont be accessing it anymore you can leave it on the server for now!
I would then Install SMF again ,add modules or any add ons you need.
Then
Install Joomla!
You can use fantastico for both....
Then
Dump the SMF forum data base tables into the Joomla Data base tables (SQL tables)
Add a New user (SMF's SQL Account password etc) to Joomla's tables (You will find the password and account name in SMF config file
Test SMF is working correctly! (Joomla will have no issues with this)
If so you should have SMF and Joomla in one SQL data base (joom1)
This makes backups 100% faster, it keeps it all together and helps solve data base access errors found in some components
So Joomla has access rights to SMF tables and SMF has access to Joomla Tables automatically.
OK backend done....
I don't know if you need the Orstio Bridge with Rocketthemes SMF templates....If so, It's so easy to set up I could get my Brother to do it....(And that's saying something)
Also, Save the content from Tiny Portal to a text file (Microsoft use Note pad!)
You can quickly recompile that in Joomla!.
Any images used within the current website TINY portal content should all be saved to a folder.
eg
This image is hidden for guests.
Please log in or register to see it.
Once in there you can upload the lot or simply transfer (much faster) to the Joomla! Images / stories folder, inlcuding any sub folders. From there you can use the Joomla editor (I would use jce and JOgadgets, mmm yummy) to quickly with just 3 clicks, add the lot to the freshly recompiled content, only this time you can tab it, pop it up, make it do things,,,,,
(firefox paiste in the editor is CTL + V)
Hope that sheds some light on the matter....
Should take around 4 hours including SMF data dump to set up Joomla with SMF
The rest depends on you...
You can re-create the site style by editing the Joomla content.html.php file to include the divisions (not tables) for the 3 or 4 images to wrap content windows...its easy to do, if you have patience and time....(patience for IE)
AFAIK that's the only way to add wrapped style like yours to Joomla Content. Modules are easy~