The specs are worn off of the flyrod, which I consider to be medium light, at 8 feet long.
You will probably get several resposes to your inquiry from others here.
Each rod is generally matched to a fly line...Your rod has a weight i.e. 4, 5, 6 weight etc. You purchase a line for it of the same weight. So, if your rod is a 5 weight, you need a 5 weight line. Double Taper is fine. The idea here is that normally on smaller streams you only use the front end of the line. Once it is worn you can turn the line around and use the opposite end...
If the weight marking is worn off you will need to experiment...Maybe take it to a fly shop or club and try different lines until the correct weight is discovered...Then you will be able to match line with the rod. This could be causing some of your casting problems with the collapsing leader etc.
It never hurts to take lessons...All of us, no matter how long we have fished are learning new wrinkles to the casting puzzle.
A leader is attached to the end of your fly line and they are sold as 4x, 5x, 6x etc...This means that the end of the fly leader can be matched to the fly size you are using. The old general rule is called, "the rule of 3" and you just divide the hook size by 3 and the terminal end of your fly line should match, give or take...A size 12 hook equals a size 4x terminal end for your leader or tippet. (12 divided by 3= 4x)
Tippet is extra leader material that you can knot to the end of the leader to make adjustments as you switch flies or need to repair the leader...
I'll leave it at that for now..."Permanent butts" vs "looped ends" etc I'll leave to the "new-schoolers" here...:)
Spence
Sorry John...We were at the answer at the same time. :)