I have a 4300lb t-bird with a basically stock 390 with a cruise-o-matic trans and 3:00 to 1 rear. I am looking to just start off a little better. I know I can't and don't want to race this car. would a higher stall speed converter make any difference or should I go with more gear? what would be a good ratio for cruising.  

It depends on cruising destination. If you are going to cruise around town, I would look at 3.50-4.11 gear range. If you are wanting to cruise on road trips, I would lean higher. If town only, I like the 4.11. Just my opinion. Falcon67 can probably give you better advice than I can, especially on stalls.  

No offense intended Falcon67. You are just pretty sharp on these Fords.  

That's a lot of weight to move!!  If you want stoplight to stoplight, then 4.11's.  You will also need a 3500 stall.  What has been done to the 390?  Is it stock?  4 bbl? What kind of intake?  Everything ties together to make one package work.  The gears and stall will get you started, but the engine needs to be setup too.  

The engine has stock cam, 9.7 to 1 flat forged aluminum pistons, edelbrock intake, 650 holley with vacum secondaies. It is basically stock and I am just looking to start off better, not race. I was told that a higher stall speed would help with that. thanks  

I would put your money into the rearend first, then stall.  If your running a stock single track 2.90 gear, a stall is not going to help much.  A good 3.50-4.11 gear posi would be your best bet.  I imagine you have a 9 inch in the t-bird, so this will let you have several choices on gears.  A stall speed will get you to your RPM range faster, but with a stock cam, that is probably around 1,000RPM, so a faster stall speed will not do much.  If you were running a good cam around 2,500RPM - 6,500RPM, then a stall converter would get you to your good horsepower (starting at 2,500RPM) faster.  Unless your planning on building a 400 plus motor a good 9 inch posi will work, otherwise I would go with a Detroit Locker, N Case housing.  I think a 3.90 gear would be ideal for what your looking for.  Be sure to have it setup by a shop, unless you know how to and have the tools to set backlash ect...
I would pull the 3rd member (pumpkin) out and take it with your new gears to the shop.

John  

I am offended that someone would think I'd take offense to some offending statement that I didn't see.  What were we talking about?

You would get some performance improvement out of a converter - but you would want to speak with an experience converter supplier about your specific deal.  I use Art Carr and Broader Performance for most of my things and I have had good luck with TCI converters too.  With all that weight, you could use more gear.  3.25~3.50 would be fine for a street car.  That and a street type 11" converter would seem to help.  If the engine has not has any performance upgrades, you'll want to stay within 500 RPM or so of the stock stall.  Cam and intake upgrades are typically what would happen before you go very far into the converter upgrade path.