It all depends on your budget. How much are you looking to spend because of course - you get what you pay for. If you want to go all out you're going to want 3 things:
1) KYB AGX struts paired with Vogtland springs (you should also replace the strut mounts).

2) Upgrade to heavier duty swaybars and putting on strut tower braces (you should also check your tie rods, ball joints, hub bearings, etc... to make sure they're not loose which they probably are if its a higher mileage car).

3) Tires would be the last thing - you want something with a stiff sidewall or even better upgrade to 18" wheels and put on 245/45/18 tires which have less sidewall = better cornerning.