You get what you pay for. Systems with high end parts with low prices are to be viewed with suspicion. They have to cut corners somewhere to get the price down. What cost you less today is going to cost you more tomorrow.
All laptops or desktops have pretty much the same CPU, GPU, ram, hard drive and screen. Most people do not know that the brand of the hard drive can make all the differences in the world. Intel and AMD make the best CPU. AMD and Nividia make the best GPU. What makes a good laptop or desktop is the manufacturing process, the motherboard and the sub components used in them. After that, it is the software included with them. Some manufactures modify Windows and the drivers severely and cripple the system into being locked to them. Some manufactures so load the system up with bloat software that it takes an hour or more just to get it off the hard drive. You will find those who do not know much about PC and laptops claiming brand do not matter. That they all have the same components in them. The brands makes all the difference. It would be like saying the brand of car, or television does not matter.
I would go with HP or ASUS.
The link below has a list of lappies that should fit your needs. Sadly most of these come with Windows 10 but a few HP have 7 loaded on them.
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&IsNodeId=1&N=100006740%2050001315%2050001186%204023%20600489658%20600546710%20600555766%20600287179%20600439628%20600471807%20600323024%20600487990%20600555764%20600555758%20600551625%20600361797%20600337813%20600371972%20600338054%20600454479%20600451669%20600452795%20600452222%20600472949%20600452559%20600488591%20600516081%20600516076%20600516082%20600560483%20601115537%20600514113%204814%20601107895%20600003988%20600003982%204084%20600470742%20601107893%204085
My opinion on the different brands.
Apple makes a good quality laptop. The problem comes when it requires service or minor upgrades. It is near impossible to do anything with them. They even glue the battery and hard drive down so you can not change it. They solder the ram to the logic board so you can not increase it. They lock up most of the software so your stuck with what they approve.
Lenovo has serious stand behind their product problems. They bought IBM PC division and proceeded to drive the quality of the system into the ground. Their customer service is well below par. They even makes Dell customer service look good. Lenovo will not allow people to read instruction on how to access the BIOS menu or to get info on their puters on their web site unless you connect to them thru Facebook. They do this so they can spy on their users. The last and final thing to remember about them is they are a Chinese Government own company. It is up to you if you want to trust them. Lenovo also got caught shipping system with Adware installed on them called Visual Discovery by Superfish. It was a giant security hole that they intentionally installed for corporate greed.
http://www.wired.com/2015/02/lenovo-superfish/
http://www.extremetech.com/computing/199628-lenovo-officially-responds-to-superfish-releases-list-of-affected-systems
Toshiba, Panasonic, Sony should be avoided because of their heavy modification of Windows and the drivers. If you remove some of the bloat they install, you can cripple the system.
Acer, Gateway, and eMachines should be avoided period. Low end system that are driving the race to the bottom.
Dell once made a good system and fell from grace. They are now struggling to regain their place in the market. Customer service is one of many problems with this company.
Alienware are glorified Dells and are more name than product. Priced extremely high for what you get. They do perform but you can get the same for less by looking around, just not packaged to be eye candy to the gamers.
Samsung has a history of using cheap parts in critical areas. Capacitors has been one area Samsung has a known history of going cheap, causing units to fail early. For that reason I would avoid them.
ASUS and HP do not modify Windows as bad as the other manufacturers. They have excellent build quality. They might add a lot of bloat but they also makes it easy to get rid of it. Their customer support and technical service is far better then the others and they have excellent online support. I have dealt with many companies when it comes to this kind of support and these two stand out.
Ultrabooks are the higher end of Wintel laptops but they have some of the same concerns as Apple. They make it next to impossible to change any hardware in them. Service of them will have to be done by the manufacturers. With most of them, you can not change your own battery or hard drive. They are designed to catch your eye but they are not any more special then other laptops except for the fact that they are slim or thin. Your paying for it being thin and slim. For the money your going to spend on it you can buy a much better laptop with more power.
Chrome books are useless. They are designed by Google to make you dependent on Google.
Hybrids are the worse of the worse. The flip or detachable touch screens are just a disaster waiting to happen.
Never buy an All In One. They are far worst then laptops of any kind to service and they have a higher failure rate.
Always avoid refurbished units. They only come with a 90 day warranty and have a higher failure rate. The service contacts are normally just a one time replace contract.
Choose wisely.