Should i get a new case?

will i get better air flow from a newer case?

Yes, you will get much better airflow from an upgrade.

This is the case I recommend to you the most:
http://www.amazon.com/SILVERSTONE-RV02B-W-Steel-Tower-C...

It has some of the best aircooling on the market.

Here are a few more that are good:
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

http://www.amazon.com/TEMPEST-EVO-POWER-BLACK-INTERIOR/...

If you are looking to improve air flow, I would look to get the Cooler Master 922, which is under $90 on Newegg.com. Your case looks pretty nice but is slightly outdated compared to some of the newer cases.

does the tempest come with dust filters?

From what I've seen, the Tempest EVO has dust filters but I would go with the Cooler Master HAF 922 in that price range... IMO

The HAF series is really overrated, and the 922 especially so. All the cases I suggested will cool better.

the tempest evo looks nice but do the top fans have filters?

IMO Thermaltake cases have very poor quality build.. Upgrading should fetch you a case with a better build quality and airflow.. I'd recommend the Lancool PC K-62.. Its a Lian-Li subsidiary and exhibits nice build quality along with very good toolless features and airflow..

Exhaust fans don't really need filters, its the intake fans that do.

true

are there any full tower cases for $100 or less

Not that are worth anything really.

The Cooler Master HAF 922 or Cooler Master CM690 II Adanced are about as close to a full without being a full size you can get.

how good is the antec 900 case?

Antec 900 is a great case. It is one of the most popular cases of all times. It is a little outdated in the cable management but still performs among the best out. (Antec 902 is the updated version)

The Antec 900 is pretty poor, I own one. I really can't recommend it. The cable management, design, material, and build quality are all below that of most other cases in the price range, Cooler Master does much better.

A decent full tower for $100:
http://www.newegg.com/Product/ProductList.aspx?Submit=E...

Either, they just have different colors, are good cases. The build quality is decent, the materials are decent, cable management is decent, cooling is good, and price is good. Your choice.