Oops, didn't see this before my post above. I assume you mean spinning when you say open face. I use mostly Shimano reels that were in the $25 to $40 range and they are fine reels. In fact I only own one freshwater reel that cost me over $40. You can get yourself a $300 reel and still encounter tangles. They happen for a number of reasons.
#1 is line twist. If you are using spinners (or any rotating lure) it will twist your line and make tangles a near certainty.For lures that rotate get some good quality, ball bearing swivels. That will cut down on line twist.
Also if when you first loaded the line on your spinning reel, if you did it wrong you had line twist before you even made your first cast. Make sure you spool your line properly (see Youtube for videos).
Even with these precautions you are still going to get line twist. It's one of the negatives of spinning reels. At the end of a day of fishing, cut off any terminal tackle and let the line out behind your boat as if you are trolling. This will help get out the twist. If you don't have a boat, let it out in to the current of the stream.
#2 major reason for tangles is slack line. This is a technique issue. Do everything you can to avoid extra slack in your line.
A third reason for tangles is that you are using the wrong line for your reel. If your reel says it is for 4-12 test line don't spool it with 15 lb test line as it will want to jump off the spool.
Another is too much line on your spool. This will cause tangles. But don't use too little line either or it will cut down you your casting distance (see below)
When you say it "doesn't cast very well" it isn't necessarily the equipment. My $25 Berkley Lightning Rod, purchased at WalMart, casts every bit as well as my $150 Shimano rods. I can cast quite well with the $15 Wally world rod I bought for my wife.
When you say it doesn't cast well, I assume you mean distance. This could happen for a number of reasons.
1. Unbalanced tackle. Line, rod or reel are not compatible. if you are casting 20 lb test line with a rod that is rated for 12 lb test it will effect your distance. If your reel is too large for the rod it will also impact your distance.
2. Rod/reel/line not appropriate for the bait you are using. Don't try to toss 3/8 oz baits using a rod that is rated for 1/2 oz. plus. Similarly, don't use a 1 oz jig on a rod that is meant for lures up to 1/2 oz. Nor are you going to get much distance using a balsa Rapala with a MH rod and 15 lb test line.
3. Not enough line on your spool. If your spool is not full, there will be friction from get go that will cut down on your casting distance. Be sure your spool is full (but not too full, see above).
4. Unmatched rod and reel. I wish I had a buck for every person I saw fishing with a spinning reel on a bait casting rod. The guides on a spinning rod are wider toward the bottom than they are on a casting rod. They act to funnel the line as it comes off the spool in a wide arc. If you use a bait casting rod with its more narrow lower guides it's just going to create friction and cut down on your casting distance.
Note: if you have a bait caster rather than a spinning reel, some, but not all of the above applies.
Don't think better equpment will be a panacea for your issues. Unless you address the root causes you can shell out $200 or $300 for a high end outfit and still wind up with the same problems.